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SUPPLEMENTARY MATERIAL
1 Synthesis and single crystal solution of the Organic Structure Directing
Agent (OSDA)
2 Study of the self-assembling of the OSDA by Photoluminiscence
spectroscopy
3 Synthesis of ITQ-29 zeolites
4 Structure refinement of SiGe-LTA and pure silica LTA
5 Comparison of commercial LTA samples with ITQ-29 zeolites
1
1 Synthesis and single crystal solution of the Organic Structure-
Directing Agent
a Synthesis of the structure directing agent
The preparation of the starting amine followed a general synthetic
procedure previously described in the literature [H Katayama E Abe K
Kaneko J Heterocyclic Chem (1982) 19 925-926]
47 g of aniline (005 mol) 212 g of sodium carbonate (02 mol) and
1264 g of 1-bromo-3-chloropropane (075 mol) were added to a reaction vessel
equipped with magnetic stirring and a condenser The reaction mixture was
heated with vigorous stirring under nitrogen atmosphere by increasing gradually
the temperature (from 70ordmC during 1h to 160ordmC for 24h) After cooling the
solution was basified with NaOH and extracted with 3 portions of ether The
organic extracts were collected washed with water and treated with 2N
hydrochloric acid The resulting acidic extract was basified with NaOH and
extracted with ether The ether extract was washed with brine and dried over
anhydrous Na2SO4 The solvent was evaporated under reduced pressure to
give the amine in 85 yield The amine was quaternized with methyl iodide as
follows A 250 ml round bottom flask was charged with 10 g (00578 mol) of
amine and 100 ml of CHCl3 A solution of 245 g (0173 mol) of methyl iodide
was added and the reaction mixture was stirred at room temperature for three
days then new excess of methyl iodide (0173 mol) was added and stirred at
room temperature for 3 days After 3 days new excess of methyl iodide (0173
mol) was added and stirred at room temperature for three days After this time a
2
solid was collected by filtration washed exhaustively with ether and dried The
resulting ammonium salt was obtained in 897 yield
Characterization data 13C-NMR (200 MHz CD3OD) 1755 2517 5242
65051305413122131821407 ppm
Anal Calcd for C13H18NI() C495 H57 N44
Found C496 H58 N45
b Single crystal solution of the structure directing agent (OSDA)
The structure of the 4-methyl-2367-tetrahydro-1H5H-pirido[321-ij]-
quinolinium was determined by single crystal diffraction
Crystallographic data Formula [C13H18N]+I H2O Triclinic space group P1 a =
107663(2) Aring b = 135874(3) Aring c = 180131(4) Aring = 79993(2)ordm =
89723(2)ordm = 89564(2)ordm V = 259489(9) Aring3 Z = 8 (CuK) = 154178 Aring
A colourless single crystal of approximate dimensions 028 026
018 mm with prismatic shape was mounted on a glass fibber and transferred to
a Bruker SMART 6K CCD area-detector three-circle diffractometer with a MAC
Science Co Ltd Rotating Anode (Cu K radiation = 154178 Aring) generator
equipped with Goebel mirrors at settings of 50 kV and 100 mA X-Ray data
were collected at 100K with a combination of seven runs at different and 2
angles 4200 frames The data were collected using 03ordm wide scans (5
3
secframe at 2 = 40ordm and 15 secframe at 2 = 100ordm ) crystal-to-detector
distance of 40 cm
The substantial redundancy in data allows empirical absorption
corrections (SADABS) to be applied using multiple measurements of symmetry-
equivalent reflections (Ratio of minimum to maximum apparent transmission
0572573) A total number of 18657 reflections were collected with 8322
independent reflections (Rint = 00456 and Rsigma = 00561) The unit cell
parameters were obtained by full-matrix least-squares refinements of 8832
reflections
Crystallographic details are given in the attached OSDAcif file
The raw intensity data frames were integrated with the SAINT program
which also applied corrections for Lorentz and polarization effects
The software package SHELXTL version 610 was used for space group
determination structure solution and refinement The structure was solved by
direct methods (SHELXS-97) completed with difference Fourier syntheses and
refined with full-matrix least-squares using SHELXL-97 minimizing (F02 ndash Fc
2)2
Weighted R factors (Rw) and all goodness of fit S are based on F2 conventional
R factors (R) are based on F All non-hydrogen atoms were refined with
anisotropic displacement parameters All scattering factors and anomalous
dispersions factors are contained in the SHELXTL 610 program library The
hydrogen atom positions were calculated geometrically and were allowed to ride
on their parent carbon atoms with fixed isotropic U
The most streaking feature of the structure directing agent is that the
organic cations appear as two self-assembled moieties by an interaction
4
between aromatic rings that trend to locate parallel one respect each other at a
distance of approximately 2 Aring as it is presented in figure 1A
Figure 1A Molecular simulation for the structure of minimum energy
References
Bruker AXS SHELXTL version 610 Structure Determination Package Bruker
AXS 2000 Madison WI
Sheldrick GM SHELXS-97 Program for Structure Solution Acta Crystallogr
Sect A 1990 46 467
Sheldrick GM SHELXL-97 Program for Crystal Structure Refinement
Universitaumlt Goumlttingen 1997
Sheldrick GM SADABS version 203 a Program for Empirical Absorption
Correction Universitaumlt Goumlttingen 1997-2001
SAINT+ NT ver 604 SAX Area-Detector Integration Program Bruker AXS
1997-2001 Madison WI
SMART v 5625 Area-Detector Software Package Bruker AXS 1997-2001
Madison WI
5
2 Study of the self-assembling of the OSDA by Photoluminiscence
spectroscopy
A UV-Vis Spectra of the OSDA in water solution The inset shows the
appearance of a new band that is assigned to the dimer formation which
increases as the OSDA concentration does (see reference 16 of the
manuscript)
6
B Photoluminescence spectrum (ex=265 nm) of the diluted OSDA in water
solution (1middot10-4 M) purged with nitrogen showing a single emission band
at approx 300 nm which is assigned to the OSDA as monomer
7
Monomer
C Photoluminiscence spectrum (ex=265 nm) of the 03 M OSDA aqueous
solution as hydroxide (This is the same concentration than that used for
the synthesis of ITQ-29) It is observed the presence of an intense
emission band at ca 450 nm The red-shift with respect to the monomer
spectrum has been attributed to the presence of π-stacking interactions
between adjacent aromatic rings (ref 16)
8
D Solid state Photoluminiscence spectrum (ex=265 nm) of the Iodide salt
of the OSDA It is seen that this spectrum is very similar to that obtained
in concentrated solution Since single crystal diffraction has shown that
the OSDA crystallised as dimers (see part 1 of this supplementary
material) we can unambiguously assigned the observed red-shift of the
emission to the π-stacking interactions between neighbored aromatic
rings Also the same interpretation could be valid for the most
concentrated aqueous solution (spectrum shown above)
9
300 400 500
80000
120000
160000
200000
Cou
nts
(au
)
Wavelength (nm)
E Solid state Photoluminiscence spectrum (ex=265 nm) of a ITQ-29 zeolite
(sample SR346b) in the as-prepared form
It is observed the presence of two emission bands at ca 310 and 430 nm
which were assigned to the OSDA as monomer and dimer respectively The
highest intensity of the second band indicates that most of the OSDA is
located inside of the ITQ-29 pores forming self-assembled dimers This is
further supported by chemical analyses and 13C-CP-MAS-NMR
spectroscopy (see supplementary material 3)
10
3 Synthesis and characterization of ITQ-29 zeolites
I Detailed synthesis methods
a) Al-free ITQ-29 (sample SR346B) was synthesized in fluoride media in the
presence of Ge from a gel of the following molar composition
067 SiO2 033 GeO2 05 ROH 05 HF 7 H2O
The gel was prepared by hydrolyzing tetraethylorthosilicate (TEOS) in an
aqueous solution of 4-methyl-2367-tetrahydro-1H5H-pyrido[321-ij]
quinolinium hydroxide (ROH) then the appropriate amount of GeO2 was added
and the mixture was kept under stirring until the ethanol formed upon hydrolysis
of TEOS and the appropriate excess of water were evaporated to reach the gel
composition given above Finally an aqueous solution of HF (50) was added
and the mixture was introduced in a Teflon-lined stainless autoclave and heated
at 150ordmC for 5 days
After this time the autoclave was cooled down and the mixture was
filtered washed with water and dried at 100ordmC The final composition is given in
Table 1 The zeolite was calcined at 700ordmC in air
b) Al-containing ITQ-29 (sample SR386B) was synthesized in fluoride media in
the presence of Ge from a gel of the following composition
067 SiO2 033 GeO2 002 Al2O3 05 ROH 05 HF 7 H2O
11
The gel preparation was similar to that described for the Al-free ITQ-29
with the addition of Al isopropoxide as the source of Al and seeds of ITQ-29
(5 of the total inorganic oxides) in order to promote the crystallization
The crystallization was also carried out at 150ordmC for 5 days The final
composition is given in Table 1
c) The high Al content ITQ-29 zeolite (sample SR408A) was synthesized using
a mixture of OSDAacutes the quinolinium derivative and tetramethylammonium It
was obtained from a gel of the following composition
067 SiO2 033 GeO2 007 Al2O3 025 ROH 025 TMAOH 05 HF 7 H2O
The gel was prepared in a similar way than the previously described but adding
the required amount of tetraethylamonium hydroxide (TAMOH) together with the
quinolinium derivative hydroxide and seeds (5 of the total inorganic oxides) in
order to promote the crystallization The synthesis was carried out at 150ordmC for
3 days The final composition is given in Table 1
d) Purely siliceous ITQ-29 (sample SR455C) was prepared in fluoride media
from a gel of the following composition
100 SiO2 025 ROH 025 TMAOH 05 HF 2 H2O
The gel was prepared as described for SR346B but the addition of GeO2
was skipped and the crystallization was done at 135ordmC for 7 days The final
composition is given in table 1 The zeolite obtained was calcined at 700ordmC in
air
12
e) The Al-ITQ-29 zeolite employed for the catalytic experiments (Sample
SR454A) was synthesized from a gel of the following composition
091 SiO2 009 GeO2 002 Al2O3 025 ROH 025 TMAOH 05 HF 3 H2O
The crystallization was performed at 135ordmC for 2 days The final composition is
given in Table 1
The zeolite was previously calcined at 580ordmC for 3 hours in air flow
before the catalytic experiments
f) Pure silicoaluminate ITQ-29 zeolite (sample SR452B) was synthesized using
a mixture of OSDAacutes the quinolinium derivative and tetramethylammonium It
was obtained from a gel of the following composition
100 SiO2 001 Al2O3 025 ROH 025 TMAOH 05 HF 3 H2O
The gel was prepared in a similar way than the previously described but adding
the required amount of tetraethylamonium hydroxide (TMAOH) together with the
quinolinium derivative hydroxide and seeds of pure silica LTA (10 of the total
inorganic oxides) in order to promote the crystallization The synthesis was
carried out at 135ordmC for 5 days The final composition is given in Table 1
The XRD pattern shows that Al-ITQ-29 was obtained with a small impurity of
RUB-10 The Al-MAS-NMR spectrum shows a single resonance at approx 55
ppm indicating the tetrahedral coordination of Al in the sample Also this
sample when calcined was able to interact with ammonia and acetonitrile
showing the accessibility of the acid sites for small molecules
13
II Chemical analyses and 13 C-CP-MAS-NMR spectroscopy characterization
results
The chemical compositions of the ITQ-29 samples described above are given in
Table 1
Table 1 Chemical compositions of ITQ-29 samples expressed as molar composition per unit cellSample Si
(uc)Ge (uc)
Al (uc)
C (uc)
N(uc)
F(uc)
OSDA(uc)
TMA(uc)
SR346B 164 76 --- 278 21 20 21(a) 0
SR386B 155 82 03 284 23 16 23(a) 0
SR408A 145 78 17 305 31 10 20(b) 10
SR455C 240 --- --- 282 30 20 18(b) 12
SR454A 207 21 12 312 30 12 21(b) 09
SR452B 235 --- 05 294 33 18 18(b) 15
(a) Calculated from the N content
(b) Calculated from the N and C contents and assuming no decomposition of
the OSDA
14
Figure 3a 13C-CP-MAS-NMR spectra of the as-prepared ITQ-29 zeolites indicates the spinning side bands
The 13C-NMR spectra indicate that the OSDA remains nearly intact within
the pores of the ITQ-29 zeolites as deduced from the close resemblance of the
solid NMR spectra and the liquid phase spectrum of an aqueous solution of the
OSDA In the spectra of the samples prepared in presence of TMAOH a new
signal at 58 ppm (marked as ) appears indicating that TMA+ cations are
incorporated into the solids Finally some minor decomposition products are
also detected (marked as )
15
4 Structure Refinement of SiGe-LTA and pure silica LTA
Structure refinement of Ge containing ITQ-29 sample (SiGe = 2)
The calcined sample with SiGe molar ratio of 21 was measured in
vacuum and the corresponding X ray powder diffraction (XRD) pattern is shown
in Figure 4a This pattern was also indexed according to a cubic unit cell with
refined cell parameter equal to 120157(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
According to the refined scattering power at the T site and assuming that it is
filled the unit cell composition of the calcined sample is Si166 Ge74 O48 ie the
refined SiGe ratio is 22 The averaged distance (d) and angles ( ) from the
tetrahedron are d(T-O)=162Aring (O-T-O) =1094ordm (T-O-T) = 1531ordm The
refined atomic coordinates are listed in Table 2 and Figure 4a shows the very
good agreement between observed and calculated XRD patterns The details of
the Rietveld refinement are given in the Experimental Section
Table 2 Fractional atomic coordinates[ab] for ITQ-29 (SiGe=22)
Atom x y z No of positions
Wyckoff notation
T[c] 03700(1) 01840(1) 0 24 k
O1 12 02118(5) 0 12 h
O2 02946(5) 02946(5) 0 12 i
O3 03370(3) 01095(4) 01095(4) 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=120157(4)Aring)[b] Estimated standard deviations given in parentheses[c] Refined atomic occupations for site T 069(2)Si+031(2)Ge
16
Figure 4a Observed (crosses) and calculated (lines) XRD patterns of ITQ-29 as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections The arrows indicate the tow small regions excluded from the Rietveld refinement containing the diffraction lines of the platinum sample holder (Cu K12 radiation)
Structure refinement of pure silica ITQ-29 sample
The purely siliceous sample was measured after calcination at 700ordmC
under air and the corresponding X ray powder diffraction (XRD) pattern is
shown in Figure 4b This pattern was indexed according to a cubic unit cell with
refined cell parameter equal to 118671(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
The refined atomic coordinates are given in Table 3 and Figure 4b shows the
very good agreement between observed and calculated XRD patterns which
confirms that ITQ-29 has LTA structure type
17
Table 3 Fractional atomic coordinates[ab] for pure silica ITQ-29
Atom x y z No of positions
Wyckoff notation
Si 03683(3) 01847(3) 0 24 k
O1 12 02179(7) 0 12 h
O2 02939(7) x 0 12 i
O3 03429(4) 01098(7) y 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=118671(4)Aring)[b] Estimated standard deviations given in parentheses
Figure 4b Observed (crosses) and calculated (lines) XRD patterns of pure silica zeolite A as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections (Cu K12 radiation) To emphasize the high angle portion of the pattern the first reflection has been cut at half height
The refined unit cell volume is shorter by 64 Aring3 than the volume found for
the Ge containing form (ie 1671 Aring3 in front of 1735 Aring3) This result is consistent
with the larger ionic radius of Ge compared to Si that is also responsible of the
larger averaged T-O distance obtained in the Ge zeolite (d(T-O)=162Aring) than in
18
the pure silica ITQ-29 material (d(Si-O)=160Aring) The averaged distance (d) and
angles ( ) from the tetrahedron are d(Si-O)=160Aring (O-Si-O) = 1094ordm (Si-
O-Si) = 1533ordm It is notorious (see Table 4) that the most tensioned Si-O-Si
angle is the Si-O2-Si angle (1584ordm) which correspond to the oxygen that is
linking to neighboured D4R cages On the other hand the Si-O-Si angles
corresponding to oxygen atoms placed at that small D4R cage do not seem to
be strongly constrained giving Si-O1-Si and Si-O3-Si angles of 1517 and
1497ordm respectively
Table 4 Bond distances in Aring and bond angles in (ordm) with esds in parentheses
for pure Si zeolite A
Si - O1 1612(5)Si - O2 1568(7)Si - O3 1606(7) (2x)O1 - Si - O2 1102(4)O1 - Si - O3 1085(5) (2x)O2 - Si - O3 1106(6) (2x)O3 - Si - O3 1085(7)Si - O1 -Si 1517(6)Si- O2 - Si 1584(9)Si - O3 - Si 1497(9)
The details of the Rietveld refinement are given in the Experimental Section
Experimental section
XRD
The Ge containing ITQ-29 sample was calcined at 700ordmC for 1 hour The
pattern was measured at room temperature in vacuum on a Philips XPert
diffractometer with Bragg-Brentano geometry using a Pt sample holder and an
19
XCelerator detector Intensity data obtained with fixed divergence slit (025ordm)
Cu K radiation ( = 15406 15444Aring) Tube voltage and intensity 45 kV and
40 mA Step size and time 0017ordm 2 and 6000s
The pure silica ITQ-29 sample was calcined at 700ordmC in air for 3 hours
The pattern was measured at room temperature on a Philips XPert
diffractometer with Bragg-Brentano geometry using a conventional flat stage
holder and an XCelerator detector Intensity data obtained with fixed
divergence slit (0125ordm) Cu K radiation ( = 15406 15444Aring) Tube voltage
and intensity 45 kV and 40 mA Step size and time 0017ordm 2 and 6000s
Rietveld refinement
The Rietveld refinement of Ge-ITQ-29 data was performed with LSP7
using a 2 range from 135ordm to 642ordm with the regions between 39344 - 40177
and 45701 - 47220 excluded due to the appearance in these regions of the
(111) and (200) Pt diffraction peaks of the sample holder The transmission
coefficient at the Pt(111) Bragg position is 035 which was used for correcting
the finite film thickness of the sample Number of contributing reflections is 86
No geometric restraints used Number of structural parameters is 7 Number of
profile parameters is 8 including unit cell parameters and zero shift (-0020ordm 2)
with visually estimated background (Average background = 38000 counts)
Profile function used was Pearson VII Refined overall thermal vibration
coefficient B = 60Aring2 The residuals of the refinement were Rwp=0026
Rp=0018 2=50
The Rietveld refinement of the pure silica-ITQ-29 data with LSP7 was
performed using the measured 2 range from 5ordm to 75ordm Number of contributing
20
reflections is 186 No geometric restraints used Number of structural
parameters is 7 Number of profile parameters is 8 including unit cell
parameters and zero shift (-0055ordm 2) with visually estimated background
(Average background = 400 counts) Profile function used was Pearson VII
Refined overall thermal vibration coefficient B = 07Aring2 The residuals of the
refinement were Rwp=0097 Rp=0062 RB=0032 2=28
21
5 Comparison of commercial LTA samples with ITQ-29 zeolites
The XRD patterns of different commercial LTA zeolites are given for
comparison purposes
Zeolite 3A is the potassium form of the LTA zeolite having the following
composition
06 K2O 040 Na2O 1 Al2O3 20 plusmn 01SiO2 x H2O
4A is the same zeolite but in the sodium its formula is
1 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
Finally 5A is the Ca2+ exchanged material with the following composition
080 CaO 020 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
(all of them were purchased from Aldrich Co)
As can be seen all the commercial LTA samples posses a framework SiAl ratio
close to 1
22
In the figure It can be seen there that the peak intensities greatly depend on the
nature of the exchanged cation located within the cavities of the LTA structure
Also the X-ray diffraction lines of pure silica ITQ-29 zeolite are shifted towards
low 2θ values (ie higher d spacing) due to the smaller ionic radii of Si than that
of Al However the formation of pure silica LTA can be unambiguously
confirmed from the absence of non assigned diffraction lines and the goodness
of Rietveld refinement
23
- SUPPLEMENTARY MATERIAL
-
1 Synthesis and single crystal solution of the Organic Structure-
Directing Agent
a Synthesis of the structure directing agent
The preparation of the starting amine followed a general synthetic
procedure previously described in the literature [H Katayama E Abe K
Kaneko J Heterocyclic Chem (1982) 19 925-926]
47 g of aniline (005 mol) 212 g of sodium carbonate (02 mol) and
1264 g of 1-bromo-3-chloropropane (075 mol) were added to a reaction vessel
equipped with magnetic stirring and a condenser The reaction mixture was
heated with vigorous stirring under nitrogen atmosphere by increasing gradually
the temperature (from 70ordmC during 1h to 160ordmC for 24h) After cooling the
solution was basified with NaOH and extracted with 3 portions of ether The
organic extracts were collected washed with water and treated with 2N
hydrochloric acid The resulting acidic extract was basified with NaOH and
extracted with ether The ether extract was washed with brine and dried over
anhydrous Na2SO4 The solvent was evaporated under reduced pressure to
give the amine in 85 yield The amine was quaternized with methyl iodide as
follows A 250 ml round bottom flask was charged with 10 g (00578 mol) of
amine and 100 ml of CHCl3 A solution of 245 g (0173 mol) of methyl iodide
was added and the reaction mixture was stirred at room temperature for three
days then new excess of methyl iodide (0173 mol) was added and stirred at
room temperature for 3 days After 3 days new excess of methyl iodide (0173
mol) was added and stirred at room temperature for three days After this time a
2
solid was collected by filtration washed exhaustively with ether and dried The
resulting ammonium salt was obtained in 897 yield
Characterization data 13C-NMR (200 MHz CD3OD) 1755 2517 5242
65051305413122131821407 ppm
Anal Calcd for C13H18NI() C495 H57 N44
Found C496 H58 N45
b Single crystal solution of the structure directing agent (OSDA)
The structure of the 4-methyl-2367-tetrahydro-1H5H-pirido[321-ij]-
quinolinium was determined by single crystal diffraction
Crystallographic data Formula [C13H18N]+I H2O Triclinic space group P1 a =
107663(2) Aring b = 135874(3) Aring c = 180131(4) Aring = 79993(2)ordm =
89723(2)ordm = 89564(2)ordm V = 259489(9) Aring3 Z = 8 (CuK) = 154178 Aring
A colourless single crystal of approximate dimensions 028 026
018 mm with prismatic shape was mounted on a glass fibber and transferred to
a Bruker SMART 6K CCD area-detector three-circle diffractometer with a MAC
Science Co Ltd Rotating Anode (Cu K radiation = 154178 Aring) generator
equipped with Goebel mirrors at settings of 50 kV and 100 mA X-Ray data
were collected at 100K with a combination of seven runs at different and 2
angles 4200 frames The data were collected using 03ordm wide scans (5
3
secframe at 2 = 40ordm and 15 secframe at 2 = 100ordm ) crystal-to-detector
distance of 40 cm
The substantial redundancy in data allows empirical absorption
corrections (SADABS) to be applied using multiple measurements of symmetry-
equivalent reflections (Ratio of minimum to maximum apparent transmission
0572573) A total number of 18657 reflections were collected with 8322
independent reflections (Rint = 00456 and Rsigma = 00561) The unit cell
parameters were obtained by full-matrix least-squares refinements of 8832
reflections
Crystallographic details are given in the attached OSDAcif file
The raw intensity data frames were integrated with the SAINT program
which also applied corrections for Lorentz and polarization effects
The software package SHELXTL version 610 was used for space group
determination structure solution and refinement The structure was solved by
direct methods (SHELXS-97) completed with difference Fourier syntheses and
refined with full-matrix least-squares using SHELXL-97 minimizing (F02 ndash Fc
2)2
Weighted R factors (Rw) and all goodness of fit S are based on F2 conventional
R factors (R) are based on F All non-hydrogen atoms were refined with
anisotropic displacement parameters All scattering factors and anomalous
dispersions factors are contained in the SHELXTL 610 program library The
hydrogen atom positions were calculated geometrically and were allowed to ride
on their parent carbon atoms with fixed isotropic U
The most streaking feature of the structure directing agent is that the
organic cations appear as two self-assembled moieties by an interaction
4
between aromatic rings that trend to locate parallel one respect each other at a
distance of approximately 2 Aring as it is presented in figure 1A
Figure 1A Molecular simulation for the structure of minimum energy
References
Bruker AXS SHELXTL version 610 Structure Determination Package Bruker
AXS 2000 Madison WI
Sheldrick GM SHELXS-97 Program for Structure Solution Acta Crystallogr
Sect A 1990 46 467
Sheldrick GM SHELXL-97 Program for Crystal Structure Refinement
Universitaumlt Goumlttingen 1997
Sheldrick GM SADABS version 203 a Program for Empirical Absorption
Correction Universitaumlt Goumlttingen 1997-2001
SAINT+ NT ver 604 SAX Area-Detector Integration Program Bruker AXS
1997-2001 Madison WI
SMART v 5625 Area-Detector Software Package Bruker AXS 1997-2001
Madison WI
5
2 Study of the self-assembling of the OSDA by Photoluminiscence
spectroscopy
A UV-Vis Spectra of the OSDA in water solution The inset shows the
appearance of a new band that is assigned to the dimer formation which
increases as the OSDA concentration does (see reference 16 of the
manuscript)
6
B Photoluminescence spectrum (ex=265 nm) of the diluted OSDA in water
solution (1middot10-4 M) purged with nitrogen showing a single emission band
at approx 300 nm which is assigned to the OSDA as monomer
7
Monomer
C Photoluminiscence spectrum (ex=265 nm) of the 03 M OSDA aqueous
solution as hydroxide (This is the same concentration than that used for
the synthesis of ITQ-29) It is observed the presence of an intense
emission band at ca 450 nm The red-shift with respect to the monomer
spectrum has been attributed to the presence of π-stacking interactions
between adjacent aromatic rings (ref 16)
8
D Solid state Photoluminiscence spectrum (ex=265 nm) of the Iodide salt
of the OSDA It is seen that this spectrum is very similar to that obtained
in concentrated solution Since single crystal diffraction has shown that
the OSDA crystallised as dimers (see part 1 of this supplementary
material) we can unambiguously assigned the observed red-shift of the
emission to the π-stacking interactions between neighbored aromatic
rings Also the same interpretation could be valid for the most
concentrated aqueous solution (spectrum shown above)
9
300 400 500
80000
120000
160000
200000
Cou
nts
(au
)
Wavelength (nm)
E Solid state Photoluminiscence spectrum (ex=265 nm) of a ITQ-29 zeolite
(sample SR346b) in the as-prepared form
It is observed the presence of two emission bands at ca 310 and 430 nm
which were assigned to the OSDA as monomer and dimer respectively The
highest intensity of the second band indicates that most of the OSDA is
located inside of the ITQ-29 pores forming self-assembled dimers This is
further supported by chemical analyses and 13C-CP-MAS-NMR
spectroscopy (see supplementary material 3)
10
3 Synthesis and characterization of ITQ-29 zeolites
I Detailed synthesis methods
a) Al-free ITQ-29 (sample SR346B) was synthesized in fluoride media in the
presence of Ge from a gel of the following molar composition
067 SiO2 033 GeO2 05 ROH 05 HF 7 H2O
The gel was prepared by hydrolyzing tetraethylorthosilicate (TEOS) in an
aqueous solution of 4-methyl-2367-tetrahydro-1H5H-pyrido[321-ij]
quinolinium hydroxide (ROH) then the appropriate amount of GeO2 was added
and the mixture was kept under stirring until the ethanol formed upon hydrolysis
of TEOS and the appropriate excess of water were evaporated to reach the gel
composition given above Finally an aqueous solution of HF (50) was added
and the mixture was introduced in a Teflon-lined stainless autoclave and heated
at 150ordmC for 5 days
After this time the autoclave was cooled down and the mixture was
filtered washed with water and dried at 100ordmC The final composition is given in
Table 1 The zeolite was calcined at 700ordmC in air
b) Al-containing ITQ-29 (sample SR386B) was synthesized in fluoride media in
the presence of Ge from a gel of the following composition
067 SiO2 033 GeO2 002 Al2O3 05 ROH 05 HF 7 H2O
11
The gel preparation was similar to that described for the Al-free ITQ-29
with the addition of Al isopropoxide as the source of Al and seeds of ITQ-29
(5 of the total inorganic oxides) in order to promote the crystallization
The crystallization was also carried out at 150ordmC for 5 days The final
composition is given in Table 1
c) The high Al content ITQ-29 zeolite (sample SR408A) was synthesized using
a mixture of OSDAacutes the quinolinium derivative and tetramethylammonium It
was obtained from a gel of the following composition
067 SiO2 033 GeO2 007 Al2O3 025 ROH 025 TMAOH 05 HF 7 H2O
The gel was prepared in a similar way than the previously described but adding
the required amount of tetraethylamonium hydroxide (TAMOH) together with the
quinolinium derivative hydroxide and seeds (5 of the total inorganic oxides) in
order to promote the crystallization The synthesis was carried out at 150ordmC for
3 days The final composition is given in Table 1
d) Purely siliceous ITQ-29 (sample SR455C) was prepared in fluoride media
from a gel of the following composition
100 SiO2 025 ROH 025 TMAOH 05 HF 2 H2O
The gel was prepared as described for SR346B but the addition of GeO2
was skipped and the crystallization was done at 135ordmC for 7 days The final
composition is given in table 1 The zeolite obtained was calcined at 700ordmC in
air
12
e) The Al-ITQ-29 zeolite employed for the catalytic experiments (Sample
SR454A) was synthesized from a gel of the following composition
091 SiO2 009 GeO2 002 Al2O3 025 ROH 025 TMAOH 05 HF 3 H2O
The crystallization was performed at 135ordmC for 2 days The final composition is
given in Table 1
The zeolite was previously calcined at 580ordmC for 3 hours in air flow
before the catalytic experiments
f) Pure silicoaluminate ITQ-29 zeolite (sample SR452B) was synthesized using
a mixture of OSDAacutes the quinolinium derivative and tetramethylammonium It
was obtained from a gel of the following composition
100 SiO2 001 Al2O3 025 ROH 025 TMAOH 05 HF 3 H2O
The gel was prepared in a similar way than the previously described but adding
the required amount of tetraethylamonium hydroxide (TMAOH) together with the
quinolinium derivative hydroxide and seeds of pure silica LTA (10 of the total
inorganic oxides) in order to promote the crystallization The synthesis was
carried out at 135ordmC for 5 days The final composition is given in Table 1
The XRD pattern shows that Al-ITQ-29 was obtained with a small impurity of
RUB-10 The Al-MAS-NMR spectrum shows a single resonance at approx 55
ppm indicating the tetrahedral coordination of Al in the sample Also this
sample when calcined was able to interact with ammonia and acetonitrile
showing the accessibility of the acid sites for small molecules
13
II Chemical analyses and 13 C-CP-MAS-NMR spectroscopy characterization
results
The chemical compositions of the ITQ-29 samples described above are given in
Table 1
Table 1 Chemical compositions of ITQ-29 samples expressed as molar composition per unit cellSample Si
(uc)Ge (uc)
Al (uc)
C (uc)
N(uc)
F(uc)
OSDA(uc)
TMA(uc)
SR346B 164 76 --- 278 21 20 21(a) 0
SR386B 155 82 03 284 23 16 23(a) 0
SR408A 145 78 17 305 31 10 20(b) 10
SR455C 240 --- --- 282 30 20 18(b) 12
SR454A 207 21 12 312 30 12 21(b) 09
SR452B 235 --- 05 294 33 18 18(b) 15
(a) Calculated from the N content
(b) Calculated from the N and C contents and assuming no decomposition of
the OSDA
14
Figure 3a 13C-CP-MAS-NMR spectra of the as-prepared ITQ-29 zeolites indicates the spinning side bands
The 13C-NMR spectra indicate that the OSDA remains nearly intact within
the pores of the ITQ-29 zeolites as deduced from the close resemblance of the
solid NMR spectra and the liquid phase spectrum of an aqueous solution of the
OSDA In the spectra of the samples prepared in presence of TMAOH a new
signal at 58 ppm (marked as ) appears indicating that TMA+ cations are
incorporated into the solids Finally some minor decomposition products are
also detected (marked as )
15
4 Structure Refinement of SiGe-LTA and pure silica LTA
Structure refinement of Ge containing ITQ-29 sample (SiGe = 2)
The calcined sample with SiGe molar ratio of 21 was measured in
vacuum and the corresponding X ray powder diffraction (XRD) pattern is shown
in Figure 4a This pattern was also indexed according to a cubic unit cell with
refined cell parameter equal to 120157(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
According to the refined scattering power at the T site and assuming that it is
filled the unit cell composition of the calcined sample is Si166 Ge74 O48 ie the
refined SiGe ratio is 22 The averaged distance (d) and angles ( ) from the
tetrahedron are d(T-O)=162Aring (O-T-O) =1094ordm (T-O-T) = 1531ordm The
refined atomic coordinates are listed in Table 2 and Figure 4a shows the very
good agreement between observed and calculated XRD patterns The details of
the Rietveld refinement are given in the Experimental Section
Table 2 Fractional atomic coordinates[ab] for ITQ-29 (SiGe=22)
Atom x y z No of positions
Wyckoff notation
T[c] 03700(1) 01840(1) 0 24 k
O1 12 02118(5) 0 12 h
O2 02946(5) 02946(5) 0 12 i
O3 03370(3) 01095(4) 01095(4) 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=120157(4)Aring)[b] Estimated standard deviations given in parentheses[c] Refined atomic occupations for site T 069(2)Si+031(2)Ge
16
Figure 4a Observed (crosses) and calculated (lines) XRD patterns of ITQ-29 as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections The arrows indicate the tow small regions excluded from the Rietveld refinement containing the diffraction lines of the platinum sample holder (Cu K12 radiation)
Structure refinement of pure silica ITQ-29 sample
The purely siliceous sample was measured after calcination at 700ordmC
under air and the corresponding X ray powder diffraction (XRD) pattern is
shown in Figure 4b This pattern was indexed according to a cubic unit cell with
refined cell parameter equal to 118671(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
The refined atomic coordinates are given in Table 3 and Figure 4b shows the
very good agreement between observed and calculated XRD patterns which
confirms that ITQ-29 has LTA structure type
17
Table 3 Fractional atomic coordinates[ab] for pure silica ITQ-29
Atom x y z No of positions
Wyckoff notation
Si 03683(3) 01847(3) 0 24 k
O1 12 02179(7) 0 12 h
O2 02939(7) x 0 12 i
O3 03429(4) 01098(7) y 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=118671(4)Aring)[b] Estimated standard deviations given in parentheses
Figure 4b Observed (crosses) and calculated (lines) XRD patterns of pure silica zeolite A as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections (Cu K12 radiation) To emphasize the high angle portion of the pattern the first reflection has been cut at half height
The refined unit cell volume is shorter by 64 Aring3 than the volume found for
the Ge containing form (ie 1671 Aring3 in front of 1735 Aring3) This result is consistent
with the larger ionic radius of Ge compared to Si that is also responsible of the
larger averaged T-O distance obtained in the Ge zeolite (d(T-O)=162Aring) than in
18
the pure silica ITQ-29 material (d(Si-O)=160Aring) The averaged distance (d) and
angles ( ) from the tetrahedron are d(Si-O)=160Aring (O-Si-O) = 1094ordm (Si-
O-Si) = 1533ordm It is notorious (see Table 4) that the most tensioned Si-O-Si
angle is the Si-O2-Si angle (1584ordm) which correspond to the oxygen that is
linking to neighboured D4R cages On the other hand the Si-O-Si angles
corresponding to oxygen atoms placed at that small D4R cage do not seem to
be strongly constrained giving Si-O1-Si and Si-O3-Si angles of 1517 and
1497ordm respectively
Table 4 Bond distances in Aring and bond angles in (ordm) with esds in parentheses
for pure Si zeolite A
Si - O1 1612(5)Si - O2 1568(7)Si - O3 1606(7) (2x)O1 - Si - O2 1102(4)O1 - Si - O3 1085(5) (2x)O2 - Si - O3 1106(6) (2x)O3 - Si - O3 1085(7)Si - O1 -Si 1517(6)Si- O2 - Si 1584(9)Si - O3 - Si 1497(9)
The details of the Rietveld refinement are given in the Experimental Section
Experimental section
XRD
The Ge containing ITQ-29 sample was calcined at 700ordmC for 1 hour The
pattern was measured at room temperature in vacuum on a Philips XPert
diffractometer with Bragg-Brentano geometry using a Pt sample holder and an
19
XCelerator detector Intensity data obtained with fixed divergence slit (025ordm)
Cu K radiation ( = 15406 15444Aring) Tube voltage and intensity 45 kV and
40 mA Step size and time 0017ordm 2 and 6000s
The pure silica ITQ-29 sample was calcined at 700ordmC in air for 3 hours
The pattern was measured at room temperature on a Philips XPert
diffractometer with Bragg-Brentano geometry using a conventional flat stage
holder and an XCelerator detector Intensity data obtained with fixed
divergence slit (0125ordm) Cu K radiation ( = 15406 15444Aring) Tube voltage
and intensity 45 kV and 40 mA Step size and time 0017ordm 2 and 6000s
Rietveld refinement
The Rietveld refinement of Ge-ITQ-29 data was performed with LSP7
using a 2 range from 135ordm to 642ordm with the regions between 39344 - 40177
and 45701 - 47220 excluded due to the appearance in these regions of the
(111) and (200) Pt diffraction peaks of the sample holder The transmission
coefficient at the Pt(111) Bragg position is 035 which was used for correcting
the finite film thickness of the sample Number of contributing reflections is 86
No geometric restraints used Number of structural parameters is 7 Number of
profile parameters is 8 including unit cell parameters and zero shift (-0020ordm 2)
with visually estimated background (Average background = 38000 counts)
Profile function used was Pearson VII Refined overall thermal vibration
coefficient B = 60Aring2 The residuals of the refinement were Rwp=0026
Rp=0018 2=50
The Rietveld refinement of the pure silica-ITQ-29 data with LSP7 was
performed using the measured 2 range from 5ordm to 75ordm Number of contributing
20
reflections is 186 No geometric restraints used Number of structural
parameters is 7 Number of profile parameters is 8 including unit cell
parameters and zero shift (-0055ordm 2) with visually estimated background
(Average background = 400 counts) Profile function used was Pearson VII
Refined overall thermal vibration coefficient B = 07Aring2 The residuals of the
refinement were Rwp=0097 Rp=0062 RB=0032 2=28
21
5 Comparison of commercial LTA samples with ITQ-29 zeolites
The XRD patterns of different commercial LTA zeolites are given for
comparison purposes
Zeolite 3A is the potassium form of the LTA zeolite having the following
composition
06 K2O 040 Na2O 1 Al2O3 20 plusmn 01SiO2 x H2O
4A is the same zeolite but in the sodium its formula is
1 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
Finally 5A is the Ca2+ exchanged material with the following composition
080 CaO 020 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
(all of them were purchased from Aldrich Co)
As can be seen all the commercial LTA samples posses a framework SiAl ratio
close to 1
22
In the figure It can be seen there that the peak intensities greatly depend on the
nature of the exchanged cation located within the cavities of the LTA structure
Also the X-ray diffraction lines of pure silica ITQ-29 zeolite are shifted towards
low 2θ values (ie higher d spacing) due to the smaller ionic radii of Si than that
of Al However the formation of pure silica LTA can be unambiguously
confirmed from the absence of non assigned diffraction lines and the goodness
of Rietveld refinement
23
- SUPPLEMENTARY MATERIAL
-
solid was collected by filtration washed exhaustively with ether and dried The
resulting ammonium salt was obtained in 897 yield
Characterization data 13C-NMR (200 MHz CD3OD) 1755 2517 5242
65051305413122131821407 ppm
Anal Calcd for C13H18NI() C495 H57 N44
Found C496 H58 N45
b Single crystal solution of the structure directing agent (OSDA)
The structure of the 4-methyl-2367-tetrahydro-1H5H-pirido[321-ij]-
quinolinium was determined by single crystal diffraction
Crystallographic data Formula [C13H18N]+I H2O Triclinic space group P1 a =
107663(2) Aring b = 135874(3) Aring c = 180131(4) Aring = 79993(2)ordm =
89723(2)ordm = 89564(2)ordm V = 259489(9) Aring3 Z = 8 (CuK) = 154178 Aring
A colourless single crystal of approximate dimensions 028 026
018 mm with prismatic shape was mounted on a glass fibber and transferred to
a Bruker SMART 6K CCD area-detector three-circle diffractometer with a MAC
Science Co Ltd Rotating Anode (Cu K radiation = 154178 Aring) generator
equipped with Goebel mirrors at settings of 50 kV and 100 mA X-Ray data
were collected at 100K with a combination of seven runs at different and 2
angles 4200 frames The data were collected using 03ordm wide scans (5
3
secframe at 2 = 40ordm and 15 secframe at 2 = 100ordm ) crystal-to-detector
distance of 40 cm
The substantial redundancy in data allows empirical absorption
corrections (SADABS) to be applied using multiple measurements of symmetry-
equivalent reflections (Ratio of minimum to maximum apparent transmission
0572573) A total number of 18657 reflections were collected with 8322
independent reflections (Rint = 00456 and Rsigma = 00561) The unit cell
parameters were obtained by full-matrix least-squares refinements of 8832
reflections
Crystallographic details are given in the attached OSDAcif file
The raw intensity data frames were integrated with the SAINT program
which also applied corrections for Lorentz and polarization effects
The software package SHELXTL version 610 was used for space group
determination structure solution and refinement The structure was solved by
direct methods (SHELXS-97) completed with difference Fourier syntheses and
refined with full-matrix least-squares using SHELXL-97 minimizing (F02 ndash Fc
2)2
Weighted R factors (Rw) and all goodness of fit S are based on F2 conventional
R factors (R) are based on F All non-hydrogen atoms were refined with
anisotropic displacement parameters All scattering factors and anomalous
dispersions factors are contained in the SHELXTL 610 program library The
hydrogen atom positions were calculated geometrically and were allowed to ride
on their parent carbon atoms with fixed isotropic U
The most streaking feature of the structure directing agent is that the
organic cations appear as two self-assembled moieties by an interaction
4
between aromatic rings that trend to locate parallel one respect each other at a
distance of approximately 2 Aring as it is presented in figure 1A
Figure 1A Molecular simulation for the structure of minimum energy
References
Bruker AXS SHELXTL version 610 Structure Determination Package Bruker
AXS 2000 Madison WI
Sheldrick GM SHELXS-97 Program for Structure Solution Acta Crystallogr
Sect A 1990 46 467
Sheldrick GM SHELXL-97 Program for Crystal Structure Refinement
Universitaumlt Goumlttingen 1997
Sheldrick GM SADABS version 203 a Program for Empirical Absorption
Correction Universitaumlt Goumlttingen 1997-2001
SAINT+ NT ver 604 SAX Area-Detector Integration Program Bruker AXS
1997-2001 Madison WI
SMART v 5625 Area-Detector Software Package Bruker AXS 1997-2001
Madison WI
5
2 Study of the self-assembling of the OSDA by Photoluminiscence
spectroscopy
A UV-Vis Spectra of the OSDA in water solution The inset shows the
appearance of a new band that is assigned to the dimer formation which
increases as the OSDA concentration does (see reference 16 of the
manuscript)
6
B Photoluminescence spectrum (ex=265 nm) of the diluted OSDA in water
solution (1middot10-4 M) purged with nitrogen showing a single emission band
at approx 300 nm which is assigned to the OSDA as monomer
7
Monomer
C Photoluminiscence spectrum (ex=265 nm) of the 03 M OSDA aqueous
solution as hydroxide (This is the same concentration than that used for
the synthesis of ITQ-29) It is observed the presence of an intense
emission band at ca 450 nm The red-shift with respect to the monomer
spectrum has been attributed to the presence of π-stacking interactions
between adjacent aromatic rings (ref 16)
8
D Solid state Photoluminiscence spectrum (ex=265 nm) of the Iodide salt
of the OSDA It is seen that this spectrum is very similar to that obtained
in concentrated solution Since single crystal diffraction has shown that
the OSDA crystallised as dimers (see part 1 of this supplementary
material) we can unambiguously assigned the observed red-shift of the
emission to the π-stacking interactions between neighbored aromatic
rings Also the same interpretation could be valid for the most
concentrated aqueous solution (spectrum shown above)
9
300 400 500
80000
120000
160000
200000
Cou
nts
(au
)
Wavelength (nm)
E Solid state Photoluminiscence spectrum (ex=265 nm) of a ITQ-29 zeolite
(sample SR346b) in the as-prepared form
It is observed the presence of two emission bands at ca 310 and 430 nm
which were assigned to the OSDA as monomer and dimer respectively The
highest intensity of the second band indicates that most of the OSDA is
located inside of the ITQ-29 pores forming self-assembled dimers This is
further supported by chemical analyses and 13C-CP-MAS-NMR
spectroscopy (see supplementary material 3)
10
3 Synthesis and characterization of ITQ-29 zeolites
I Detailed synthesis methods
a) Al-free ITQ-29 (sample SR346B) was synthesized in fluoride media in the
presence of Ge from a gel of the following molar composition
067 SiO2 033 GeO2 05 ROH 05 HF 7 H2O
The gel was prepared by hydrolyzing tetraethylorthosilicate (TEOS) in an
aqueous solution of 4-methyl-2367-tetrahydro-1H5H-pyrido[321-ij]
quinolinium hydroxide (ROH) then the appropriate amount of GeO2 was added
and the mixture was kept under stirring until the ethanol formed upon hydrolysis
of TEOS and the appropriate excess of water were evaporated to reach the gel
composition given above Finally an aqueous solution of HF (50) was added
and the mixture was introduced in a Teflon-lined stainless autoclave and heated
at 150ordmC for 5 days
After this time the autoclave was cooled down and the mixture was
filtered washed with water and dried at 100ordmC The final composition is given in
Table 1 The zeolite was calcined at 700ordmC in air
b) Al-containing ITQ-29 (sample SR386B) was synthesized in fluoride media in
the presence of Ge from a gel of the following composition
067 SiO2 033 GeO2 002 Al2O3 05 ROH 05 HF 7 H2O
11
The gel preparation was similar to that described for the Al-free ITQ-29
with the addition of Al isopropoxide as the source of Al and seeds of ITQ-29
(5 of the total inorganic oxides) in order to promote the crystallization
The crystallization was also carried out at 150ordmC for 5 days The final
composition is given in Table 1
c) The high Al content ITQ-29 zeolite (sample SR408A) was synthesized using
a mixture of OSDAacutes the quinolinium derivative and tetramethylammonium It
was obtained from a gel of the following composition
067 SiO2 033 GeO2 007 Al2O3 025 ROH 025 TMAOH 05 HF 7 H2O
The gel was prepared in a similar way than the previously described but adding
the required amount of tetraethylamonium hydroxide (TAMOH) together with the
quinolinium derivative hydroxide and seeds (5 of the total inorganic oxides) in
order to promote the crystallization The synthesis was carried out at 150ordmC for
3 days The final composition is given in Table 1
d) Purely siliceous ITQ-29 (sample SR455C) was prepared in fluoride media
from a gel of the following composition
100 SiO2 025 ROH 025 TMAOH 05 HF 2 H2O
The gel was prepared as described for SR346B but the addition of GeO2
was skipped and the crystallization was done at 135ordmC for 7 days The final
composition is given in table 1 The zeolite obtained was calcined at 700ordmC in
air
12
e) The Al-ITQ-29 zeolite employed for the catalytic experiments (Sample
SR454A) was synthesized from a gel of the following composition
091 SiO2 009 GeO2 002 Al2O3 025 ROH 025 TMAOH 05 HF 3 H2O
The crystallization was performed at 135ordmC for 2 days The final composition is
given in Table 1
The zeolite was previously calcined at 580ordmC for 3 hours in air flow
before the catalytic experiments
f) Pure silicoaluminate ITQ-29 zeolite (sample SR452B) was synthesized using
a mixture of OSDAacutes the quinolinium derivative and tetramethylammonium It
was obtained from a gel of the following composition
100 SiO2 001 Al2O3 025 ROH 025 TMAOH 05 HF 3 H2O
The gel was prepared in a similar way than the previously described but adding
the required amount of tetraethylamonium hydroxide (TMAOH) together with the
quinolinium derivative hydroxide and seeds of pure silica LTA (10 of the total
inorganic oxides) in order to promote the crystallization The synthesis was
carried out at 135ordmC for 5 days The final composition is given in Table 1
The XRD pattern shows that Al-ITQ-29 was obtained with a small impurity of
RUB-10 The Al-MAS-NMR spectrum shows a single resonance at approx 55
ppm indicating the tetrahedral coordination of Al in the sample Also this
sample when calcined was able to interact with ammonia and acetonitrile
showing the accessibility of the acid sites for small molecules
13
II Chemical analyses and 13 C-CP-MAS-NMR spectroscopy characterization
results
The chemical compositions of the ITQ-29 samples described above are given in
Table 1
Table 1 Chemical compositions of ITQ-29 samples expressed as molar composition per unit cellSample Si
(uc)Ge (uc)
Al (uc)
C (uc)
N(uc)
F(uc)
OSDA(uc)
TMA(uc)
SR346B 164 76 --- 278 21 20 21(a) 0
SR386B 155 82 03 284 23 16 23(a) 0
SR408A 145 78 17 305 31 10 20(b) 10
SR455C 240 --- --- 282 30 20 18(b) 12
SR454A 207 21 12 312 30 12 21(b) 09
SR452B 235 --- 05 294 33 18 18(b) 15
(a) Calculated from the N content
(b) Calculated from the N and C contents and assuming no decomposition of
the OSDA
14
Figure 3a 13C-CP-MAS-NMR spectra of the as-prepared ITQ-29 zeolites indicates the spinning side bands
The 13C-NMR spectra indicate that the OSDA remains nearly intact within
the pores of the ITQ-29 zeolites as deduced from the close resemblance of the
solid NMR spectra and the liquid phase spectrum of an aqueous solution of the
OSDA In the spectra of the samples prepared in presence of TMAOH a new
signal at 58 ppm (marked as ) appears indicating that TMA+ cations are
incorporated into the solids Finally some minor decomposition products are
also detected (marked as )
15
4 Structure Refinement of SiGe-LTA and pure silica LTA
Structure refinement of Ge containing ITQ-29 sample (SiGe = 2)
The calcined sample with SiGe molar ratio of 21 was measured in
vacuum and the corresponding X ray powder diffraction (XRD) pattern is shown
in Figure 4a This pattern was also indexed according to a cubic unit cell with
refined cell parameter equal to 120157(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
According to the refined scattering power at the T site and assuming that it is
filled the unit cell composition of the calcined sample is Si166 Ge74 O48 ie the
refined SiGe ratio is 22 The averaged distance (d) and angles ( ) from the
tetrahedron are d(T-O)=162Aring (O-T-O) =1094ordm (T-O-T) = 1531ordm The
refined atomic coordinates are listed in Table 2 and Figure 4a shows the very
good agreement between observed and calculated XRD patterns The details of
the Rietveld refinement are given in the Experimental Section
Table 2 Fractional atomic coordinates[ab] for ITQ-29 (SiGe=22)
Atom x y z No of positions
Wyckoff notation
T[c] 03700(1) 01840(1) 0 24 k
O1 12 02118(5) 0 12 h
O2 02946(5) 02946(5) 0 12 i
O3 03370(3) 01095(4) 01095(4) 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=120157(4)Aring)[b] Estimated standard deviations given in parentheses[c] Refined atomic occupations for site T 069(2)Si+031(2)Ge
16
Figure 4a Observed (crosses) and calculated (lines) XRD patterns of ITQ-29 as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections The arrows indicate the tow small regions excluded from the Rietveld refinement containing the diffraction lines of the platinum sample holder (Cu K12 radiation)
Structure refinement of pure silica ITQ-29 sample
The purely siliceous sample was measured after calcination at 700ordmC
under air and the corresponding X ray powder diffraction (XRD) pattern is
shown in Figure 4b This pattern was indexed according to a cubic unit cell with
refined cell parameter equal to 118671(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
The refined atomic coordinates are given in Table 3 and Figure 4b shows the
very good agreement between observed and calculated XRD patterns which
confirms that ITQ-29 has LTA structure type
17
Table 3 Fractional atomic coordinates[ab] for pure silica ITQ-29
Atom x y z No of positions
Wyckoff notation
Si 03683(3) 01847(3) 0 24 k
O1 12 02179(7) 0 12 h
O2 02939(7) x 0 12 i
O3 03429(4) 01098(7) y 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=118671(4)Aring)[b] Estimated standard deviations given in parentheses
Figure 4b Observed (crosses) and calculated (lines) XRD patterns of pure silica zeolite A as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections (Cu K12 radiation) To emphasize the high angle portion of the pattern the first reflection has been cut at half height
The refined unit cell volume is shorter by 64 Aring3 than the volume found for
the Ge containing form (ie 1671 Aring3 in front of 1735 Aring3) This result is consistent
with the larger ionic radius of Ge compared to Si that is also responsible of the
larger averaged T-O distance obtained in the Ge zeolite (d(T-O)=162Aring) than in
18
the pure silica ITQ-29 material (d(Si-O)=160Aring) The averaged distance (d) and
angles ( ) from the tetrahedron are d(Si-O)=160Aring (O-Si-O) = 1094ordm (Si-
O-Si) = 1533ordm It is notorious (see Table 4) that the most tensioned Si-O-Si
angle is the Si-O2-Si angle (1584ordm) which correspond to the oxygen that is
linking to neighboured D4R cages On the other hand the Si-O-Si angles
corresponding to oxygen atoms placed at that small D4R cage do not seem to
be strongly constrained giving Si-O1-Si and Si-O3-Si angles of 1517 and
1497ordm respectively
Table 4 Bond distances in Aring and bond angles in (ordm) with esds in parentheses
for pure Si zeolite A
Si - O1 1612(5)Si - O2 1568(7)Si - O3 1606(7) (2x)O1 - Si - O2 1102(4)O1 - Si - O3 1085(5) (2x)O2 - Si - O3 1106(6) (2x)O3 - Si - O3 1085(7)Si - O1 -Si 1517(6)Si- O2 - Si 1584(9)Si - O3 - Si 1497(9)
The details of the Rietveld refinement are given in the Experimental Section
Experimental section
XRD
The Ge containing ITQ-29 sample was calcined at 700ordmC for 1 hour The
pattern was measured at room temperature in vacuum on a Philips XPert
diffractometer with Bragg-Brentano geometry using a Pt sample holder and an
19
XCelerator detector Intensity data obtained with fixed divergence slit (025ordm)
Cu K radiation ( = 15406 15444Aring) Tube voltage and intensity 45 kV and
40 mA Step size and time 0017ordm 2 and 6000s
The pure silica ITQ-29 sample was calcined at 700ordmC in air for 3 hours
The pattern was measured at room temperature on a Philips XPert
diffractometer with Bragg-Brentano geometry using a conventional flat stage
holder and an XCelerator detector Intensity data obtained with fixed
divergence slit (0125ordm) Cu K radiation ( = 15406 15444Aring) Tube voltage
and intensity 45 kV and 40 mA Step size and time 0017ordm 2 and 6000s
Rietveld refinement
The Rietveld refinement of Ge-ITQ-29 data was performed with LSP7
using a 2 range from 135ordm to 642ordm with the regions between 39344 - 40177
and 45701 - 47220 excluded due to the appearance in these regions of the
(111) and (200) Pt diffraction peaks of the sample holder The transmission
coefficient at the Pt(111) Bragg position is 035 which was used for correcting
the finite film thickness of the sample Number of contributing reflections is 86
No geometric restraints used Number of structural parameters is 7 Number of
profile parameters is 8 including unit cell parameters and zero shift (-0020ordm 2)
with visually estimated background (Average background = 38000 counts)
Profile function used was Pearson VII Refined overall thermal vibration
coefficient B = 60Aring2 The residuals of the refinement were Rwp=0026
Rp=0018 2=50
The Rietveld refinement of the pure silica-ITQ-29 data with LSP7 was
performed using the measured 2 range from 5ordm to 75ordm Number of contributing
20
reflections is 186 No geometric restraints used Number of structural
parameters is 7 Number of profile parameters is 8 including unit cell
parameters and zero shift (-0055ordm 2) with visually estimated background
(Average background = 400 counts) Profile function used was Pearson VII
Refined overall thermal vibration coefficient B = 07Aring2 The residuals of the
refinement were Rwp=0097 Rp=0062 RB=0032 2=28
21
5 Comparison of commercial LTA samples with ITQ-29 zeolites
The XRD patterns of different commercial LTA zeolites are given for
comparison purposes
Zeolite 3A is the potassium form of the LTA zeolite having the following
composition
06 K2O 040 Na2O 1 Al2O3 20 plusmn 01SiO2 x H2O
4A is the same zeolite but in the sodium its formula is
1 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
Finally 5A is the Ca2+ exchanged material with the following composition
080 CaO 020 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
(all of them were purchased from Aldrich Co)
As can be seen all the commercial LTA samples posses a framework SiAl ratio
close to 1
22
In the figure It can be seen there that the peak intensities greatly depend on the
nature of the exchanged cation located within the cavities of the LTA structure
Also the X-ray diffraction lines of pure silica ITQ-29 zeolite are shifted towards
low 2θ values (ie higher d spacing) due to the smaller ionic radii of Si than that
of Al However the formation of pure silica LTA can be unambiguously
confirmed from the absence of non assigned diffraction lines and the goodness
of Rietveld refinement
23
- SUPPLEMENTARY MATERIAL
-
secframe at 2 = 40ordm and 15 secframe at 2 = 100ordm ) crystal-to-detector
distance of 40 cm
The substantial redundancy in data allows empirical absorption
corrections (SADABS) to be applied using multiple measurements of symmetry-
equivalent reflections (Ratio of minimum to maximum apparent transmission
0572573) A total number of 18657 reflections were collected with 8322
independent reflections (Rint = 00456 and Rsigma = 00561) The unit cell
parameters were obtained by full-matrix least-squares refinements of 8832
reflections
Crystallographic details are given in the attached OSDAcif file
The raw intensity data frames were integrated with the SAINT program
which also applied corrections for Lorentz and polarization effects
The software package SHELXTL version 610 was used for space group
determination structure solution and refinement The structure was solved by
direct methods (SHELXS-97) completed with difference Fourier syntheses and
refined with full-matrix least-squares using SHELXL-97 minimizing (F02 ndash Fc
2)2
Weighted R factors (Rw) and all goodness of fit S are based on F2 conventional
R factors (R) are based on F All non-hydrogen atoms were refined with
anisotropic displacement parameters All scattering factors and anomalous
dispersions factors are contained in the SHELXTL 610 program library The
hydrogen atom positions were calculated geometrically and were allowed to ride
on their parent carbon atoms with fixed isotropic U
The most streaking feature of the structure directing agent is that the
organic cations appear as two self-assembled moieties by an interaction
4
between aromatic rings that trend to locate parallel one respect each other at a
distance of approximately 2 Aring as it is presented in figure 1A
Figure 1A Molecular simulation for the structure of minimum energy
References
Bruker AXS SHELXTL version 610 Structure Determination Package Bruker
AXS 2000 Madison WI
Sheldrick GM SHELXS-97 Program for Structure Solution Acta Crystallogr
Sect A 1990 46 467
Sheldrick GM SHELXL-97 Program for Crystal Structure Refinement
Universitaumlt Goumlttingen 1997
Sheldrick GM SADABS version 203 a Program for Empirical Absorption
Correction Universitaumlt Goumlttingen 1997-2001
SAINT+ NT ver 604 SAX Area-Detector Integration Program Bruker AXS
1997-2001 Madison WI
SMART v 5625 Area-Detector Software Package Bruker AXS 1997-2001
Madison WI
5
2 Study of the self-assembling of the OSDA by Photoluminiscence
spectroscopy
A UV-Vis Spectra of the OSDA in water solution The inset shows the
appearance of a new band that is assigned to the dimer formation which
increases as the OSDA concentration does (see reference 16 of the
manuscript)
6
B Photoluminescence spectrum (ex=265 nm) of the diluted OSDA in water
solution (1middot10-4 M) purged with nitrogen showing a single emission band
at approx 300 nm which is assigned to the OSDA as monomer
7
Monomer
C Photoluminiscence spectrum (ex=265 nm) of the 03 M OSDA aqueous
solution as hydroxide (This is the same concentration than that used for
the synthesis of ITQ-29) It is observed the presence of an intense
emission band at ca 450 nm The red-shift with respect to the monomer
spectrum has been attributed to the presence of π-stacking interactions
between adjacent aromatic rings (ref 16)
8
D Solid state Photoluminiscence spectrum (ex=265 nm) of the Iodide salt
of the OSDA It is seen that this spectrum is very similar to that obtained
in concentrated solution Since single crystal diffraction has shown that
the OSDA crystallised as dimers (see part 1 of this supplementary
material) we can unambiguously assigned the observed red-shift of the
emission to the π-stacking interactions between neighbored aromatic
rings Also the same interpretation could be valid for the most
concentrated aqueous solution (spectrum shown above)
9
300 400 500
80000
120000
160000
200000
Cou
nts
(au
)
Wavelength (nm)
E Solid state Photoluminiscence spectrum (ex=265 nm) of a ITQ-29 zeolite
(sample SR346b) in the as-prepared form
It is observed the presence of two emission bands at ca 310 and 430 nm
which were assigned to the OSDA as monomer and dimer respectively The
highest intensity of the second band indicates that most of the OSDA is
located inside of the ITQ-29 pores forming self-assembled dimers This is
further supported by chemical analyses and 13C-CP-MAS-NMR
spectroscopy (see supplementary material 3)
10
3 Synthesis and characterization of ITQ-29 zeolites
I Detailed synthesis methods
a) Al-free ITQ-29 (sample SR346B) was synthesized in fluoride media in the
presence of Ge from a gel of the following molar composition
067 SiO2 033 GeO2 05 ROH 05 HF 7 H2O
The gel was prepared by hydrolyzing tetraethylorthosilicate (TEOS) in an
aqueous solution of 4-methyl-2367-tetrahydro-1H5H-pyrido[321-ij]
quinolinium hydroxide (ROH) then the appropriate amount of GeO2 was added
and the mixture was kept under stirring until the ethanol formed upon hydrolysis
of TEOS and the appropriate excess of water were evaporated to reach the gel
composition given above Finally an aqueous solution of HF (50) was added
and the mixture was introduced in a Teflon-lined stainless autoclave and heated
at 150ordmC for 5 days
After this time the autoclave was cooled down and the mixture was
filtered washed with water and dried at 100ordmC The final composition is given in
Table 1 The zeolite was calcined at 700ordmC in air
b) Al-containing ITQ-29 (sample SR386B) was synthesized in fluoride media in
the presence of Ge from a gel of the following composition
067 SiO2 033 GeO2 002 Al2O3 05 ROH 05 HF 7 H2O
11
The gel preparation was similar to that described for the Al-free ITQ-29
with the addition of Al isopropoxide as the source of Al and seeds of ITQ-29
(5 of the total inorganic oxides) in order to promote the crystallization
The crystallization was also carried out at 150ordmC for 5 days The final
composition is given in Table 1
c) The high Al content ITQ-29 zeolite (sample SR408A) was synthesized using
a mixture of OSDAacutes the quinolinium derivative and tetramethylammonium It
was obtained from a gel of the following composition
067 SiO2 033 GeO2 007 Al2O3 025 ROH 025 TMAOH 05 HF 7 H2O
The gel was prepared in a similar way than the previously described but adding
the required amount of tetraethylamonium hydroxide (TAMOH) together with the
quinolinium derivative hydroxide and seeds (5 of the total inorganic oxides) in
order to promote the crystallization The synthesis was carried out at 150ordmC for
3 days The final composition is given in Table 1
d) Purely siliceous ITQ-29 (sample SR455C) was prepared in fluoride media
from a gel of the following composition
100 SiO2 025 ROH 025 TMAOH 05 HF 2 H2O
The gel was prepared as described for SR346B but the addition of GeO2
was skipped and the crystallization was done at 135ordmC for 7 days The final
composition is given in table 1 The zeolite obtained was calcined at 700ordmC in
air
12
e) The Al-ITQ-29 zeolite employed for the catalytic experiments (Sample
SR454A) was synthesized from a gel of the following composition
091 SiO2 009 GeO2 002 Al2O3 025 ROH 025 TMAOH 05 HF 3 H2O
The crystallization was performed at 135ordmC for 2 days The final composition is
given in Table 1
The zeolite was previously calcined at 580ordmC for 3 hours in air flow
before the catalytic experiments
f) Pure silicoaluminate ITQ-29 zeolite (sample SR452B) was synthesized using
a mixture of OSDAacutes the quinolinium derivative and tetramethylammonium It
was obtained from a gel of the following composition
100 SiO2 001 Al2O3 025 ROH 025 TMAOH 05 HF 3 H2O
The gel was prepared in a similar way than the previously described but adding
the required amount of tetraethylamonium hydroxide (TMAOH) together with the
quinolinium derivative hydroxide and seeds of pure silica LTA (10 of the total
inorganic oxides) in order to promote the crystallization The synthesis was
carried out at 135ordmC for 5 days The final composition is given in Table 1
The XRD pattern shows that Al-ITQ-29 was obtained with a small impurity of
RUB-10 The Al-MAS-NMR spectrum shows a single resonance at approx 55
ppm indicating the tetrahedral coordination of Al in the sample Also this
sample when calcined was able to interact with ammonia and acetonitrile
showing the accessibility of the acid sites for small molecules
13
II Chemical analyses and 13 C-CP-MAS-NMR spectroscopy characterization
results
The chemical compositions of the ITQ-29 samples described above are given in
Table 1
Table 1 Chemical compositions of ITQ-29 samples expressed as molar composition per unit cellSample Si
(uc)Ge (uc)
Al (uc)
C (uc)
N(uc)
F(uc)
OSDA(uc)
TMA(uc)
SR346B 164 76 --- 278 21 20 21(a) 0
SR386B 155 82 03 284 23 16 23(a) 0
SR408A 145 78 17 305 31 10 20(b) 10
SR455C 240 --- --- 282 30 20 18(b) 12
SR454A 207 21 12 312 30 12 21(b) 09
SR452B 235 --- 05 294 33 18 18(b) 15
(a) Calculated from the N content
(b) Calculated from the N and C contents and assuming no decomposition of
the OSDA
14
Figure 3a 13C-CP-MAS-NMR spectra of the as-prepared ITQ-29 zeolites indicates the spinning side bands
The 13C-NMR spectra indicate that the OSDA remains nearly intact within
the pores of the ITQ-29 zeolites as deduced from the close resemblance of the
solid NMR spectra and the liquid phase spectrum of an aqueous solution of the
OSDA In the spectra of the samples prepared in presence of TMAOH a new
signal at 58 ppm (marked as ) appears indicating that TMA+ cations are
incorporated into the solids Finally some minor decomposition products are
also detected (marked as )
15
4 Structure Refinement of SiGe-LTA and pure silica LTA
Structure refinement of Ge containing ITQ-29 sample (SiGe = 2)
The calcined sample with SiGe molar ratio of 21 was measured in
vacuum and the corresponding X ray powder diffraction (XRD) pattern is shown
in Figure 4a This pattern was also indexed according to a cubic unit cell with
refined cell parameter equal to 120157(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
According to the refined scattering power at the T site and assuming that it is
filled the unit cell composition of the calcined sample is Si166 Ge74 O48 ie the
refined SiGe ratio is 22 The averaged distance (d) and angles ( ) from the
tetrahedron are d(T-O)=162Aring (O-T-O) =1094ordm (T-O-T) = 1531ordm The
refined atomic coordinates are listed in Table 2 and Figure 4a shows the very
good agreement between observed and calculated XRD patterns The details of
the Rietveld refinement are given in the Experimental Section
Table 2 Fractional atomic coordinates[ab] for ITQ-29 (SiGe=22)
Atom x y z No of positions
Wyckoff notation
T[c] 03700(1) 01840(1) 0 24 k
O1 12 02118(5) 0 12 h
O2 02946(5) 02946(5) 0 12 i
O3 03370(3) 01095(4) 01095(4) 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=120157(4)Aring)[b] Estimated standard deviations given in parentheses[c] Refined atomic occupations for site T 069(2)Si+031(2)Ge
16
Figure 4a Observed (crosses) and calculated (lines) XRD patterns of ITQ-29 as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections The arrows indicate the tow small regions excluded from the Rietveld refinement containing the diffraction lines of the platinum sample holder (Cu K12 radiation)
Structure refinement of pure silica ITQ-29 sample
The purely siliceous sample was measured after calcination at 700ordmC
under air and the corresponding X ray powder diffraction (XRD) pattern is
shown in Figure 4b This pattern was indexed according to a cubic unit cell with
refined cell parameter equal to 118671(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
The refined atomic coordinates are given in Table 3 and Figure 4b shows the
very good agreement between observed and calculated XRD patterns which
confirms that ITQ-29 has LTA structure type
17
Table 3 Fractional atomic coordinates[ab] for pure silica ITQ-29
Atom x y z No of positions
Wyckoff notation
Si 03683(3) 01847(3) 0 24 k
O1 12 02179(7) 0 12 h
O2 02939(7) x 0 12 i
O3 03429(4) 01098(7) y 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=118671(4)Aring)[b] Estimated standard deviations given in parentheses
Figure 4b Observed (crosses) and calculated (lines) XRD patterns of pure silica zeolite A as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections (Cu K12 radiation) To emphasize the high angle portion of the pattern the first reflection has been cut at half height
The refined unit cell volume is shorter by 64 Aring3 than the volume found for
the Ge containing form (ie 1671 Aring3 in front of 1735 Aring3) This result is consistent
with the larger ionic radius of Ge compared to Si that is also responsible of the
larger averaged T-O distance obtained in the Ge zeolite (d(T-O)=162Aring) than in
18
the pure silica ITQ-29 material (d(Si-O)=160Aring) The averaged distance (d) and
angles ( ) from the tetrahedron are d(Si-O)=160Aring (O-Si-O) = 1094ordm (Si-
O-Si) = 1533ordm It is notorious (see Table 4) that the most tensioned Si-O-Si
angle is the Si-O2-Si angle (1584ordm) which correspond to the oxygen that is
linking to neighboured D4R cages On the other hand the Si-O-Si angles
corresponding to oxygen atoms placed at that small D4R cage do not seem to
be strongly constrained giving Si-O1-Si and Si-O3-Si angles of 1517 and
1497ordm respectively
Table 4 Bond distances in Aring and bond angles in (ordm) with esds in parentheses
for pure Si zeolite A
Si - O1 1612(5)Si - O2 1568(7)Si - O3 1606(7) (2x)O1 - Si - O2 1102(4)O1 - Si - O3 1085(5) (2x)O2 - Si - O3 1106(6) (2x)O3 - Si - O3 1085(7)Si - O1 -Si 1517(6)Si- O2 - Si 1584(9)Si - O3 - Si 1497(9)
The details of the Rietveld refinement are given in the Experimental Section
Experimental section
XRD
The Ge containing ITQ-29 sample was calcined at 700ordmC for 1 hour The
pattern was measured at room temperature in vacuum on a Philips XPert
diffractometer with Bragg-Brentano geometry using a Pt sample holder and an
19
XCelerator detector Intensity data obtained with fixed divergence slit (025ordm)
Cu K radiation ( = 15406 15444Aring) Tube voltage and intensity 45 kV and
40 mA Step size and time 0017ordm 2 and 6000s
The pure silica ITQ-29 sample was calcined at 700ordmC in air for 3 hours
The pattern was measured at room temperature on a Philips XPert
diffractometer with Bragg-Brentano geometry using a conventional flat stage
holder and an XCelerator detector Intensity data obtained with fixed
divergence slit (0125ordm) Cu K radiation ( = 15406 15444Aring) Tube voltage
and intensity 45 kV and 40 mA Step size and time 0017ordm 2 and 6000s
Rietveld refinement
The Rietveld refinement of Ge-ITQ-29 data was performed with LSP7
using a 2 range from 135ordm to 642ordm with the regions between 39344 - 40177
and 45701 - 47220 excluded due to the appearance in these regions of the
(111) and (200) Pt diffraction peaks of the sample holder The transmission
coefficient at the Pt(111) Bragg position is 035 which was used for correcting
the finite film thickness of the sample Number of contributing reflections is 86
No geometric restraints used Number of structural parameters is 7 Number of
profile parameters is 8 including unit cell parameters and zero shift (-0020ordm 2)
with visually estimated background (Average background = 38000 counts)
Profile function used was Pearson VII Refined overall thermal vibration
coefficient B = 60Aring2 The residuals of the refinement were Rwp=0026
Rp=0018 2=50
The Rietveld refinement of the pure silica-ITQ-29 data with LSP7 was
performed using the measured 2 range from 5ordm to 75ordm Number of contributing
20
reflections is 186 No geometric restraints used Number of structural
parameters is 7 Number of profile parameters is 8 including unit cell
parameters and zero shift (-0055ordm 2) with visually estimated background
(Average background = 400 counts) Profile function used was Pearson VII
Refined overall thermal vibration coefficient B = 07Aring2 The residuals of the
refinement were Rwp=0097 Rp=0062 RB=0032 2=28
21
5 Comparison of commercial LTA samples with ITQ-29 zeolites
The XRD patterns of different commercial LTA zeolites are given for
comparison purposes
Zeolite 3A is the potassium form of the LTA zeolite having the following
composition
06 K2O 040 Na2O 1 Al2O3 20 plusmn 01SiO2 x H2O
4A is the same zeolite but in the sodium its formula is
1 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
Finally 5A is the Ca2+ exchanged material with the following composition
080 CaO 020 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
(all of them were purchased from Aldrich Co)
As can be seen all the commercial LTA samples posses a framework SiAl ratio
close to 1
22
In the figure It can be seen there that the peak intensities greatly depend on the
nature of the exchanged cation located within the cavities of the LTA structure
Also the X-ray diffraction lines of pure silica ITQ-29 zeolite are shifted towards
low 2θ values (ie higher d spacing) due to the smaller ionic radii of Si than that
of Al However the formation of pure silica LTA can be unambiguously
confirmed from the absence of non assigned diffraction lines and the goodness
of Rietveld refinement
23
- SUPPLEMENTARY MATERIAL
-
between aromatic rings that trend to locate parallel one respect each other at a
distance of approximately 2 Aring as it is presented in figure 1A
Figure 1A Molecular simulation for the structure of minimum energy
References
Bruker AXS SHELXTL version 610 Structure Determination Package Bruker
AXS 2000 Madison WI
Sheldrick GM SHELXS-97 Program for Structure Solution Acta Crystallogr
Sect A 1990 46 467
Sheldrick GM SHELXL-97 Program for Crystal Structure Refinement
Universitaumlt Goumlttingen 1997
Sheldrick GM SADABS version 203 a Program for Empirical Absorption
Correction Universitaumlt Goumlttingen 1997-2001
SAINT+ NT ver 604 SAX Area-Detector Integration Program Bruker AXS
1997-2001 Madison WI
SMART v 5625 Area-Detector Software Package Bruker AXS 1997-2001
Madison WI
5
2 Study of the self-assembling of the OSDA by Photoluminiscence
spectroscopy
A UV-Vis Spectra of the OSDA in water solution The inset shows the
appearance of a new band that is assigned to the dimer formation which
increases as the OSDA concentration does (see reference 16 of the
manuscript)
6
B Photoluminescence spectrum (ex=265 nm) of the diluted OSDA in water
solution (1middot10-4 M) purged with nitrogen showing a single emission band
at approx 300 nm which is assigned to the OSDA as monomer
7
Monomer
C Photoluminiscence spectrum (ex=265 nm) of the 03 M OSDA aqueous
solution as hydroxide (This is the same concentration than that used for
the synthesis of ITQ-29) It is observed the presence of an intense
emission band at ca 450 nm The red-shift with respect to the monomer
spectrum has been attributed to the presence of π-stacking interactions
between adjacent aromatic rings (ref 16)
8
D Solid state Photoluminiscence spectrum (ex=265 nm) of the Iodide salt
of the OSDA It is seen that this spectrum is very similar to that obtained
in concentrated solution Since single crystal diffraction has shown that
the OSDA crystallised as dimers (see part 1 of this supplementary
material) we can unambiguously assigned the observed red-shift of the
emission to the π-stacking interactions between neighbored aromatic
rings Also the same interpretation could be valid for the most
concentrated aqueous solution (spectrum shown above)
9
300 400 500
80000
120000
160000
200000
Cou
nts
(au
)
Wavelength (nm)
E Solid state Photoluminiscence spectrum (ex=265 nm) of a ITQ-29 zeolite
(sample SR346b) in the as-prepared form
It is observed the presence of two emission bands at ca 310 and 430 nm
which were assigned to the OSDA as monomer and dimer respectively The
highest intensity of the second band indicates that most of the OSDA is
located inside of the ITQ-29 pores forming self-assembled dimers This is
further supported by chemical analyses and 13C-CP-MAS-NMR
spectroscopy (see supplementary material 3)
10
3 Synthesis and characterization of ITQ-29 zeolites
I Detailed synthesis methods
a) Al-free ITQ-29 (sample SR346B) was synthesized in fluoride media in the
presence of Ge from a gel of the following molar composition
067 SiO2 033 GeO2 05 ROH 05 HF 7 H2O
The gel was prepared by hydrolyzing tetraethylorthosilicate (TEOS) in an
aqueous solution of 4-methyl-2367-tetrahydro-1H5H-pyrido[321-ij]
quinolinium hydroxide (ROH) then the appropriate amount of GeO2 was added
and the mixture was kept under stirring until the ethanol formed upon hydrolysis
of TEOS and the appropriate excess of water were evaporated to reach the gel
composition given above Finally an aqueous solution of HF (50) was added
and the mixture was introduced in a Teflon-lined stainless autoclave and heated
at 150ordmC for 5 days
After this time the autoclave was cooled down and the mixture was
filtered washed with water and dried at 100ordmC The final composition is given in
Table 1 The zeolite was calcined at 700ordmC in air
b) Al-containing ITQ-29 (sample SR386B) was synthesized in fluoride media in
the presence of Ge from a gel of the following composition
067 SiO2 033 GeO2 002 Al2O3 05 ROH 05 HF 7 H2O
11
The gel preparation was similar to that described for the Al-free ITQ-29
with the addition of Al isopropoxide as the source of Al and seeds of ITQ-29
(5 of the total inorganic oxides) in order to promote the crystallization
The crystallization was also carried out at 150ordmC for 5 days The final
composition is given in Table 1
c) The high Al content ITQ-29 zeolite (sample SR408A) was synthesized using
a mixture of OSDAacutes the quinolinium derivative and tetramethylammonium It
was obtained from a gel of the following composition
067 SiO2 033 GeO2 007 Al2O3 025 ROH 025 TMAOH 05 HF 7 H2O
The gel was prepared in a similar way than the previously described but adding
the required amount of tetraethylamonium hydroxide (TAMOH) together with the
quinolinium derivative hydroxide and seeds (5 of the total inorganic oxides) in
order to promote the crystallization The synthesis was carried out at 150ordmC for
3 days The final composition is given in Table 1
d) Purely siliceous ITQ-29 (sample SR455C) was prepared in fluoride media
from a gel of the following composition
100 SiO2 025 ROH 025 TMAOH 05 HF 2 H2O
The gel was prepared as described for SR346B but the addition of GeO2
was skipped and the crystallization was done at 135ordmC for 7 days The final
composition is given in table 1 The zeolite obtained was calcined at 700ordmC in
air
12
e) The Al-ITQ-29 zeolite employed for the catalytic experiments (Sample
SR454A) was synthesized from a gel of the following composition
091 SiO2 009 GeO2 002 Al2O3 025 ROH 025 TMAOH 05 HF 3 H2O
The crystallization was performed at 135ordmC for 2 days The final composition is
given in Table 1
The zeolite was previously calcined at 580ordmC for 3 hours in air flow
before the catalytic experiments
f) Pure silicoaluminate ITQ-29 zeolite (sample SR452B) was synthesized using
a mixture of OSDAacutes the quinolinium derivative and tetramethylammonium It
was obtained from a gel of the following composition
100 SiO2 001 Al2O3 025 ROH 025 TMAOH 05 HF 3 H2O
The gel was prepared in a similar way than the previously described but adding
the required amount of tetraethylamonium hydroxide (TMAOH) together with the
quinolinium derivative hydroxide and seeds of pure silica LTA (10 of the total
inorganic oxides) in order to promote the crystallization The synthesis was
carried out at 135ordmC for 5 days The final composition is given in Table 1
The XRD pattern shows that Al-ITQ-29 was obtained with a small impurity of
RUB-10 The Al-MAS-NMR spectrum shows a single resonance at approx 55
ppm indicating the tetrahedral coordination of Al in the sample Also this
sample when calcined was able to interact with ammonia and acetonitrile
showing the accessibility of the acid sites for small molecules
13
II Chemical analyses and 13 C-CP-MAS-NMR spectroscopy characterization
results
The chemical compositions of the ITQ-29 samples described above are given in
Table 1
Table 1 Chemical compositions of ITQ-29 samples expressed as molar composition per unit cellSample Si
(uc)Ge (uc)
Al (uc)
C (uc)
N(uc)
F(uc)
OSDA(uc)
TMA(uc)
SR346B 164 76 --- 278 21 20 21(a) 0
SR386B 155 82 03 284 23 16 23(a) 0
SR408A 145 78 17 305 31 10 20(b) 10
SR455C 240 --- --- 282 30 20 18(b) 12
SR454A 207 21 12 312 30 12 21(b) 09
SR452B 235 --- 05 294 33 18 18(b) 15
(a) Calculated from the N content
(b) Calculated from the N and C contents and assuming no decomposition of
the OSDA
14
Figure 3a 13C-CP-MAS-NMR spectra of the as-prepared ITQ-29 zeolites indicates the spinning side bands
The 13C-NMR spectra indicate that the OSDA remains nearly intact within
the pores of the ITQ-29 zeolites as deduced from the close resemblance of the
solid NMR spectra and the liquid phase spectrum of an aqueous solution of the
OSDA In the spectra of the samples prepared in presence of TMAOH a new
signal at 58 ppm (marked as ) appears indicating that TMA+ cations are
incorporated into the solids Finally some minor decomposition products are
also detected (marked as )
15
4 Structure Refinement of SiGe-LTA and pure silica LTA
Structure refinement of Ge containing ITQ-29 sample (SiGe = 2)
The calcined sample with SiGe molar ratio of 21 was measured in
vacuum and the corresponding X ray powder diffraction (XRD) pattern is shown
in Figure 4a This pattern was also indexed according to a cubic unit cell with
refined cell parameter equal to 120157(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
According to the refined scattering power at the T site and assuming that it is
filled the unit cell composition of the calcined sample is Si166 Ge74 O48 ie the
refined SiGe ratio is 22 The averaged distance (d) and angles ( ) from the
tetrahedron are d(T-O)=162Aring (O-T-O) =1094ordm (T-O-T) = 1531ordm The
refined atomic coordinates are listed in Table 2 and Figure 4a shows the very
good agreement between observed and calculated XRD patterns The details of
the Rietveld refinement are given in the Experimental Section
Table 2 Fractional atomic coordinates[ab] for ITQ-29 (SiGe=22)
Atom x y z No of positions
Wyckoff notation
T[c] 03700(1) 01840(1) 0 24 k
O1 12 02118(5) 0 12 h
O2 02946(5) 02946(5) 0 12 i
O3 03370(3) 01095(4) 01095(4) 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=120157(4)Aring)[b] Estimated standard deviations given in parentheses[c] Refined atomic occupations for site T 069(2)Si+031(2)Ge
16
Figure 4a Observed (crosses) and calculated (lines) XRD patterns of ITQ-29 as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections The arrows indicate the tow small regions excluded from the Rietveld refinement containing the diffraction lines of the platinum sample holder (Cu K12 radiation)
Structure refinement of pure silica ITQ-29 sample
The purely siliceous sample was measured after calcination at 700ordmC
under air and the corresponding X ray powder diffraction (XRD) pattern is
shown in Figure 4b This pattern was indexed according to a cubic unit cell with
refined cell parameter equal to 118671(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
The refined atomic coordinates are given in Table 3 and Figure 4b shows the
very good agreement between observed and calculated XRD patterns which
confirms that ITQ-29 has LTA structure type
17
Table 3 Fractional atomic coordinates[ab] for pure silica ITQ-29
Atom x y z No of positions
Wyckoff notation
Si 03683(3) 01847(3) 0 24 k
O1 12 02179(7) 0 12 h
O2 02939(7) x 0 12 i
O3 03429(4) 01098(7) y 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=118671(4)Aring)[b] Estimated standard deviations given in parentheses
Figure 4b Observed (crosses) and calculated (lines) XRD patterns of pure silica zeolite A as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections (Cu K12 radiation) To emphasize the high angle portion of the pattern the first reflection has been cut at half height
The refined unit cell volume is shorter by 64 Aring3 than the volume found for
the Ge containing form (ie 1671 Aring3 in front of 1735 Aring3) This result is consistent
with the larger ionic radius of Ge compared to Si that is also responsible of the
larger averaged T-O distance obtained in the Ge zeolite (d(T-O)=162Aring) than in
18
the pure silica ITQ-29 material (d(Si-O)=160Aring) The averaged distance (d) and
angles ( ) from the tetrahedron are d(Si-O)=160Aring (O-Si-O) = 1094ordm (Si-
O-Si) = 1533ordm It is notorious (see Table 4) that the most tensioned Si-O-Si
angle is the Si-O2-Si angle (1584ordm) which correspond to the oxygen that is
linking to neighboured D4R cages On the other hand the Si-O-Si angles
corresponding to oxygen atoms placed at that small D4R cage do not seem to
be strongly constrained giving Si-O1-Si and Si-O3-Si angles of 1517 and
1497ordm respectively
Table 4 Bond distances in Aring and bond angles in (ordm) with esds in parentheses
for pure Si zeolite A
Si - O1 1612(5)Si - O2 1568(7)Si - O3 1606(7) (2x)O1 - Si - O2 1102(4)O1 - Si - O3 1085(5) (2x)O2 - Si - O3 1106(6) (2x)O3 - Si - O3 1085(7)Si - O1 -Si 1517(6)Si- O2 - Si 1584(9)Si - O3 - Si 1497(9)
The details of the Rietveld refinement are given in the Experimental Section
Experimental section
XRD
The Ge containing ITQ-29 sample was calcined at 700ordmC for 1 hour The
pattern was measured at room temperature in vacuum on a Philips XPert
diffractometer with Bragg-Brentano geometry using a Pt sample holder and an
19
XCelerator detector Intensity data obtained with fixed divergence slit (025ordm)
Cu K radiation ( = 15406 15444Aring) Tube voltage and intensity 45 kV and
40 mA Step size and time 0017ordm 2 and 6000s
The pure silica ITQ-29 sample was calcined at 700ordmC in air for 3 hours
The pattern was measured at room temperature on a Philips XPert
diffractometer with Bragg-Brentano geometry using a conventional flat stage
holder and an XCelerator detector Intensity data obtained with fixed
divergence slit (0125ordm) Cu K radiation ( = 15406 15444Aring) Tube voltage
and intensity 45 kV and 40 mA Step size and time 0017ordm 2 and 6000s
Rietveld refinement
The Rietveld refinement of Ge-ITQ-29 data was performed with LSP7
using a 2 range from 135ordm to 642ordm with the regions between 39344 - 40177
and 45701 - 47220 excluded due to the appearance in these regions of the
(111) and (200) Pt diffraction peaks of the sample holder The transmission
coefficient at the Pt(111) Bragg position is 035 which was used for correcting
the finite film thickness of the sample Number of contributing reflections is 86
No geometric restraints used Number of structural parameters is 7 Number of
profile parameters is 8 including unit cell parameters and zero shift (-0020ordm 2)
with visually estimated background (Average background = 38000 counts)
Profile function used was Pearson VII Refined overall thermal vibration
coefficient B = 60Aring2 The residuals of the refinement were Rwp=0026
Rp=0018 2=50
The Rietveld refinement of the pure silica-ITQ-29 data with LSP7 was
performed using the measured 2 range from 5ordm to 75ordm Number of contributing
20
reflections is 186 No geometric restraints used Number of structural
parameters is 7 Number of profile parameters is 8 including unit cell
parameters and zero shift (-0055ordm 2) with visually estimated background
(Average background = 400 counts) Profile function used was Pearson VII
Refined overall thermal vibration coefficient B = 07Aring2 The residuals of the
refinement were Rwp=0097 Rp=0062 RB=0032 2=28
21
5 Comparison of commercial LTA samples with ITQ-29 zeolites
The XRD patterns of different commercial LTA zeolites are given for
comparison purposes
Zeolite 3A is the potassium form of the LTA zeolite having the following
composition
06 K2O 040 Na2O 1 Al2O3 20 plusmn 01SiO2 x H2O
4A is the same zeolite but in the sodium its formula is
1 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
Finally 5A is the Ca2+ exchanged material with the following composition
080 CaO 020 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
(all of them were purchased from Aldrich Co)
As can be seen all the commercial LTA samples posses a framework SiAl ratio
close to 1
22
In the figure It can be seen there that the peak intensities greatly depend on the
nature of the exchanged cation located within the cavities of the LTA structure
Also the X-ray diffraction lines of pure silica ITQ-29 zeolite are shifted towards
low 2θ values (ie higher d spacing) due to the smaller ionic radii of Si than that
of Al However the formation of pure silica LTA can be unambiguously
confirmed from the absence of non assigned diffraction lines and the goodness
of Rietveld refinement
23
- SUPPLEMENTARY MATERIAL
-
2 Study of the self-assembling of the OSDA by Photoluminiscence
spectroscopy
A UV-Vis Spectra of the OSDA in water solution The inset shows the
appearance of a new band that is assigned to the dimer formation which
increases as the OSDA concentration does (see reference 16 of the
manuscript)
6
B Photoluminescence spectrum (ex=265 nm) of the diluted OSDA in water
solution (1middot10-4 M) purged with nitrogen showing a single emission band
at approx 300 nm which is assigned to the OSDA as monomer
7
Monomer
C Photoluminiscence spectrum (ex=265 nm) of the 03 M OSDA aqueous
solution as hydroxide (This is the same concentration than that used for
the synthesis of ITQ-29) It is observed the presence of an intense
emission band at ca 450 nm The red-shift with respect to the monomer
spectrum has been attributed to the presence of π-stacking interactions
between adjacent aromatic rings (ref 16)
8
D Solid state Photoluminiscence spectrum (ex=265 nm) of the Iodide salt
of the OSDA It is seen that this spectrum is very similar to that obtained
in concentrated solution Since single crystal diffraction has shown that
the OSDA crystallised as dimers (see part 1 of this supplementary
material) we can unambiguously assigned the observed red-shift of the
emission to the π-stacking interactions between neighbored aromatic
rings Also the same interpretation could be valid for the most
concentrated aqueous solution (spectrum shown above)
9
300 400 500
80000
120000
160000
200000
Cou
nts
(au
)
Wavelength (nm)
E Solid state Photoluminiscence spectrum (ex=265 nm) of a ITQ-29 zeolite
(sample SR346b) in the as-prepared form
It is observed the presence of two emission bands at ca 310 and 430 nm
which were assigned to the OSDA as monomer and dimer respectively The
highest intensity of the second band indicates that most of the OSDA is
located inside of the ITQ-29 pores forming self-assembled dimers This is
further supported by chemical analyses and 13C-CP-MAS-NMR
spectroscopy (see supplementary material 3)
10
3 Synthesis and characterization of ITQ-29 zeolites
I Detailed synthesis methods
a) Al-free ITQ-29 (sample SR346B) was synthesized in fluoride media in the
presence of Ge from a gel of the following molar composition
067 SiO2 033 GeO2 05 ROH 05 HF 7 H2O
The gel was prepared by hydrolyzing tetraethylorthosilicate (TEOS) in an
aqueous solution of 4-methyl-2367-tetrahydro-1H5H-pyrido[321-ij]
quinolinium hydroxide (ROH) then the appropriate amount of GeO2 was added
and the mixture was kept under stirring until the ethanol formed upon hydrolysis
of TEOS and the appropriate excess of water were evaporated to reach the gel
composition given above Finally an aqueous solution of HF (50) was added
and the mixture was introduced in a Teflon-lined stainless autoclave and heated
at 150ordmC for 5 days
After this time the autoclave was cooled down and the mixture was
filtered washed with water and dried at 100ordmC The final composition is given in
Table 1 The zeolite was calcined at 700ordmC in air
b) Al-containing ITQ-29 (sample SR386B) was synthesized in fluoride media in
the presence of Ge from a gel of the following composition
067 SiO2 033 GeO2 002 Al2O3 05 ROH 05 HF 7 H2O
11
The gel preparation was similar to that described for the Al-free ITQ-29
with the addition of Al isopropoxide as the source of Al and seeds of ITQ-29
(5 of the total inorganic oxides) in order to promote the crystallization
The crystallization was also carried out at 150ordmC for 5 days The final
composition is given in Table 1
c) The high Al content ITQ-29 zeolite (sample SR408A) was synthesized using
a mixture of OSDAacutes the quinolinium derivative and tetramethylammonium It
was obtained from a gel of the following composition
067 SiO2 033 GeO2 007 Al2O3 025 ROH 025 TMAOH 05 HF 7 H2O
The gel was prepared in a similar way than the previously described but adding
the required amount of tetraethylamonium hydroxide (TAMOH) together with the
quinolinium derivative hydroxide and seeds (5 of the total inorganic oxides) in
order to promote the crystallization The synthesis was carried out at 150ordmC for
3 days The final composition is given in Table 1
d) Purely siliceous ITQ-29 (sample SR455C) was prepared in fluoride media
from a gel of the following composition
100 SiO2 025 ROH 025 TMAOH 05 HF 2 H2O
The gel was prepared as described for SR346B but the addition of GeO2
was skipped and the crystallization was done at 135ordmC for 7 days The final
composition is given in table 1 The zeolite obtained was calcined at 700ordmC in
air
12
e) The Al-ITQ-29 zeolite employed for the catalytic experiments (Sample
SR454A) was synthesized from a gel of the following composition
091 SiO2 009 GeO2 002 Al2O3 025 ROH 025 TMAOH 05 HF 3 H2O
The crystallization was performed at 135ordmC for 2 days The final composition is
given in Table 1
The zeolite was previously calcined at 580ordmC for 3 hours in air flow
before the catalytic experiments
f) Pure silicoaluminate ITQ-29 zeolite (sample SR452B) was synthesized using
a mixture of OSDAacutes the quinolinium derivative and tetramethylammonium It
was obtained from a gel of the following composition
100 SiO2 001 Al2O3 025 ROH 025 TMAOH 05 HF 3 H2O
The gel was prepared in a similar way than the previously described but adding
the required amount of tetraethylamonium hydroxide (TMAOH) together with the
quinolinium derivative hydroxide and seeds of pure silica LTA (10 of the total
inorganic oxides) in order to promote the crystallization The synthesis was
carried out at 135ordmC for 5 days The final composition is given in Table 1
The XRD pattern shows that Al-ITQ-29 was obtained with a small impurity of
RUB-10 The Al-MAS-NMR spectrum shows a single resonance at approx 55
ppm indicating the tetrahedral coordination of Al in the sample Also this
sample when calcined was able to interact with ammonia and acetonitrile
showing the accessibility of the acid sites for small molecules
13
II Chemical analyses and 13 C-CP-MAS-NMR spectroscopy characterization
results
The chemical compositions of the ITQ-29 samples described above are given in
Table 1
Table 1 Chemical compositions of ITQ-29 samples expressed as molar composition per unit cellSample Si
(uc)Ge (uc)
Al (uc)
C (uc)
N(uc)
F(uc)
OSDA(uc)
TMA(uc)
SR346B 164 76 --- 278 21 20 21(a) 0
SR386B 155 82 03 284 23 16 23(a) 0
SR408A 145 78 17 305 31 10 20(b) 10
SR455C 240 --- --- 282 30 20 18(b) 12
SR454A 207 21 12 312 30 12 21(b) 09
SR452B 235 --- 05 294 33 18 18(b) 15
(a) Calculated from the N content
(b) Calculated from the N and C contents and assuming no decomposition of
the OSDA
14
Figure 3a 13C-CP-MAS-NMR spectra of the as-prepared ITQ-29 zeolites indicates the spinning side bands
The 13C-NMR spectra indicate that the OSDA remains nearly intact within
the pores of the ITQ-29 zeolites as deduced from the close resemblance of the
solid NMR spectra and the liquid phase spectrum of an aqueous solution of the
OSDA In the spectra of the samples prepared in presence of TMAOH a new
signal at 58 ppm (marked as ) appears indicating that TMA+ cations are
incorporated into the solids Finally some minor decomposition products are
also detected (marked as )
15
4 Structure Refinement of SiGe-LTA and pure silica LTA
Structure refinement of Ge containing ITQ-29 sample (SiGe = 2)
The calcined sample with SiGe molar ratio of 21 was measured in
vacuum and the corresponding X ray powder diffraction (XRD) pattern is shown
in Figure 4a This pattern was also indexed according to a cubic unit cell with
refined cell parameter equal to 120157(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
According to the refined scattering power at the T site and assuming that it is
filled the unit cell composition of the calcined sample is Si166 Ge74 O48 ie the
refined SiGe ratio is 22 The averaged distance (d) and angles ( ) from the
tetrahedron are d(T-O)=162Aring (O-T-O) =1094ordm (T-O-T) = 1531ordm The
refined atomic coordinates are listed in Table 2 and Figure 4a shows the very
good agreement between observed and calculated XRD patterns The details of
the Rietveld refinement are given in the Experimental Section
Table 2 Fractional atomic coordinates[ab] for ITQ-29 (SiGe=22)
Atom x y z No of positions
Wyckoff notation
T[c] 03700(1) 01840(1) 0 24 k
O1 12 02118(5) 0 12 h
O2 02946(5) 02946(5) 0 12 i
O3 03370(3) 01095(4) 01095(4) 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=120157(4)Aring)[b] Estimated standard deviations given in parentheses[c] Refined atomic occupations for site T 069(2)Si+031(2)Ge
16
Figure 4a Observed (crosses) and calculated (lines) XRD patterns of ITQ-29 as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections The arrows indicate the tow small regions excluded from the Rietveld refinement containing the diffraction lines of the platinum sample holder (Cu K12 radiation)
Structure refinement of pure silica ITQ-29 sample
The purely siliceous sample was measured after calcination at 700ordmC
under air and the corresponding X ray powder diffraction (XRD) pattern is
shown in Figure 4b This pattern was indexed according to a cubic unit cell with
refined cell parameter equal to 118671(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
The refined atomic coordinates are given in Table 3 and Figure 4b shows the
very good agreement between observed and calculated XRD patterns which
confirms that ITQ-29 has LTA structure type
17
Table 3 Fractional atomic coordinates[ab] for pure silica ITQ-29
Atom x y z No of positions
Wyckoff notation
Si 03683(3) 01847(3) 0 24 k
O1 12 02179(7) 0 12 h
O2 02939(7) x 0 12 i
O3 03429(4) 01098(7) y 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=118671(4)Aring)[b] Estimated standard deviations given in parentheses
Figure 4b Observed (crosses) and calculated (lines) XRD patterns of pure silica zeolite A as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections (Cu K12 radiation) To emphasize the high angle portion of the pattern the first reflection has been cut at half height
The refined unit cell volume is shorter by 64 Aring3 than the volume found for
the Ge containing form (ie 1671 Aring3 in front of 1735 Aring3) This result is consistent
with the larger ionic radius of Ge compared to Si that is also responsible of the
larger averaged T-O distance obtained in the Ge zeolite (d(T-O)=162Aring) than in
18
the pure silica ITQ-29 material (d(Si-O)=160Aring) The averaged distance (d) and
angles ( ) from the tetrahedron are d(Si-O)=160Aring (O-Si-O) = 1094ordm (Si-
O-Si) = 1533ordm It is notorious (see Table 4) that the most tensioned Si-O-Si
angle is the Si-O2-Si angle (1584ordm) which correspond to the oxygen that is
linking to neighboured D4R cages On the other hand the Si-O-Si angles
corresponding to oxygen atoms placed at that small D4R cage do not seem to
be strongly constrained giving Si-O1-Si and Si-O3-Si angles of 1517 and
1497ordm respectively
Table 4 Bond distances in Aring and bond angles in (ordm) with esds in parentheses
for pure Si zeolite A
Si - O1 1612(5)Si - O2 1568(7)Si - O3 1606(7) (2x)O1 - Si - O2 1102(4)O1 - Si - O3 1085(5) (2x)O2 - Si - O3 1106(6) (2x)O3 - Si - O3 1085(7)Si - O1 -Si 1517(6)Si- O2 - Si 1584(9)Si - O3 - Si 1497(9)
The details of the Rietveld refinement are given in the Experimental Section
Experimental section
XRD
The Ge containing ITQ-29 sample was calcined at 700ordmC for 1 hour The
pattern was measured at room temperature in vacuum on a Philips XPert
diffractometer with Bragg-Brentano geometry using a Pt sample holder and an
19
XCelerator detector Intensity data obtained with fixed divergence slit (025ordm)
Cu K radiation ( = 15406 15444Aring) Tube voltage and intensity 45 kV and
40 mA Step size and time 0017ordm 2 and 6000s
The pure silica ITQ-29 sample was calcined at 700ordmC in air for 3 hours
The pattern was measured at room temperature on a Philips XPert
diffractometer with Bragg-Brentano geometry using a conventional flat stage
holder and an XCelerator detector Intensity data obtained with fixed
divergence slit (0125ordm) Cu K radiation ( = 15406 15444Aring) Tube voltage
and intensity 45 kV and 40 mA Step size and time 0017ordm 2 and 6000s
Rietveld refinement
The Rietveld refinement of Ge-ITQ-29 data was performed with LSP7
using a 2 range from 135ordm to 642ordm with the regions between 39344 - 40177
and 45701 - 47220 excluded due to the appearance in these regions of the
(111) and (200) Pt diffraction peaks of the sample holder The transmission
coefficient at the Pt(111) Bragg position is 035 which was used for correcting
the finite film thickness of the sample Number of contributing reflections is 86
No geometric restraints used Number of structural parameters is 7 Number of
profile parameters is 8 including unit cell parameters and zero shift (-0020ordm 2)
with visually estimated background (Average background = 38000 counts)
Profile function used was Pearson VII Refined overall thermal vibration
coefficient B = 60Aring2 The residuals of the refinement were Rwp=0026
Rp=0018 2=50
The Rietveld refinement of the pure silica-ITQ-29 data with LSP7 was
performed using the measured 2 range from 5ordm to 75ordm Number of contributing
20
reflections is 186 No geometric restraints used Number of structural
parameters is 7 Number of profile parameters is 8 including unit cell
parameters and zero shift (-0055ordm 2) with visually estimated background
(Average background = 400 counts) Profile function used was Pearson VII
Refined overall thermal vibration coefficient B = 07Aring2 The residuals of the
refinement were Rwp=0097 Rp=0062 RB=0032 2=28
21
5 Comparison of commercial LTA samples with ITQ-29 zeolites
The XRD patterns of different commercial LTA zeolites are given for
comparison purposes
Zeolite 3A is the potassium form of the LTA zeolite having the following
composition
06 K2O 040 Na2O 1 Al2O3 20 plusmn 01SiO2 x H2O
4A is the same zeolite but in the sodium its formula is
1 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
Finally 5A is the Ca2+ exchanged material with the following composition
080 CaO 020 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
(all of them were purchased from Aldrich Co)
As can be seen all the commercial LTA samples posses a framework SiAl ratio
close to 1
22
In the figure It can be seen there that the peak intensities greatly depend on the
nature of the exchanged cation located within the cavities of the LTA structure
Also the X-ray diffraction lines of pure silica ITQ-29 zeolite are shifted towards
low 2θ values (ie higher d spacing) due to the smaller ionic radii of Si than that
of Al However the formation of pure silica LTA can be unambiguously
confirmed from the absence of non assigned diffraction lines and the goodness
of Rietveld refinement
23
- SUPPLEMENTARY MATERIAL
-
B Photoluminescence spectrum (ex=265 nm) of the diluted OSDA in water
solution (1middot10-4 M) purged with nitrogen showing a single emission band
at approx 300 nm which is assigned to the OSDA as monomer
7
Monomer
C Photoluminiscence spectrum (ex=265 nm) of the 03 M OSDA aqueous
solution as hydroxide (This is the same concentration than that used for
the synthesis of ITQ-29) It is observed the presence of an intense
emission band at ca 450 nm The red-shift with respect to the monomer
spectrum has been attributed to the presence of π-stacking interactions
between adjacent aromatic rings (ref 16)
8
D Solid state Photoluminiscence spectrum (ex=265 nm) of the Iodide salt
of the OSDA It is seen that this spectrum is very similar to that obtained
in concentrated solution Since single crystal diffraction has shown that
the OSDA crystallised as dimers (see part 1 of this supplementary
material) we can unambiguously assigned the observed red-shift of the
emission to the π-stacking interactions between neighbored aromatic
rings Also the same interpretation could be valid for the most
concentrated aqueous solution (spectrum shown above)
9
300 400 500
80000
120000
160000
200000
Cou
nts
(au
)
Wavelength (nm)
E Solid state Photoluminiscence spectrum (ex=265 nm) of a ITQ-29 zeolite
(sample SR346b) in the as-prepared form
It is observed the presence of two emission bands at ca 310 and 430 nm
which were assigned to the OSDA as monomer and dimer respectively The
highest intensity of the second band indicates that most of the OSDA is
located inside of the ITQ-29 pores forming self-assembled dimers This is
further supported by chemical analyses and 13C-CP-MAS-NMR
spectroscopy (see supplementary material 3)
10
3 Synthesis and characterization of ITQ-29 zeolites
I Detailed synthesis methods
a) Al-free ITQ-29 (sample SR346B) was synthesized in fluoride media in the
presence of Ge from a gel of the following molar composition
067 SiO2 033 GeO2 05 ROH 05 HF 7 H2O
The gel was prepared by hydrolyzing tetraethylorthosilicate (TEOS) in an
aqueous solution of 4-methyl-2367-tetrahydro-1H5H-pyrido[321-ij]
quinolinium hydroxide (ROH) then the appropriate amount of GeO2 was added
and the mixture was kept under stirring until the ethanol formed upon hydrolysis
of TEOS and the appropriate excess of water were evaporated to reach the gel
composition given above Finally an aqueous solution of HF (50) was added
and the mixture was introduced in a Teflon-lined stainless autoclave and heated
at 150ordmC for 5 days
After this time the autoclave was cooled down and the mixture was
filtered washed with water and dried at 100ordmC The final composition is given in
Table 1 The zeolite was calcined at 700ordmC in air
b) Al-containing ITQ-29 (sample SR386B) was synthesized in fluoride media in
the presence of Ge from a gel of the following composition
067 SiO2 033 GeO2 002 Al2O3 05 ROH 05 HF 7 H2O
11
The gel preparation was similar to that described for the Al-free ITQ-29
with the addition of Al isopropoxide as the source of Al and seeds of ITQ-29
(5 of the total inorganic oxides) in order to promote the crystallization
The crystallization was also carried out at 150ordmC for 5 days The final
composition is given in Table 1
c) The high Al content ITQ-29 zeolite (sample SR408A) was synthesized using
a mixture of OSDAacutes the quinolinium derivative and tetramethylammonium It
was obtained from a gel of the following composition
067 SiO2 033 GeO2 007 Al2O3 025 ROH 025 TMAOH 05 HF 7 H2O
The gel was prepared in a similar way than the previously described but adding
the required amount of tetraethylamonium hydroxide (TAMOH) together with the
quinolinium derivative hydroxide and seeds (5 of the total inorganic oxides) in
order to promote the crystallization The synthesis was carried out at 150ordmC for
3 days The final composition is given in Table 1
d) Purely siliceous ITQ-29 (sample SR455C) was prepared in fluoride media
from a gel of the following composition
100 SiO2 025 ROH 025 TMAOH 05 HF 2 H2O
The gel was prepared as described for SR346B but the addition of GeO2
was skipped and the crystallization was done at 135ordmC for 7 days The final
composition is given in table 1 The zeolite obtained was calcined at 700ordmC in
air
12
e) The Al-ITQ-29 zeolite employed for the catalytic experiments (Sample
SR454A) was synthesized from a gel of the following composition
091 SiO2 009 GeO2 002 Al2O3 025 ROH 025 TMAOH 05 HF 3 H2O
The crystallization was performed at 135ordmC for 2 days The final composition is
given in Table 1
The zeolite was previously calcined at 580ordmC for 3 hours in air flow
before the catalytic experiments
f) Pure silicoaluminate ITQ-29 zeolite (sample SR452B) was synthesized using
a mixture of OSDAacutes the quinolinium derivative and tetramethylammonium It
was obtained from a gel of the following composition
100 SiO2 001 Al2O3 025 ROH 025 TMAOH 05 HF 3 H2O
The gel was prepared in a similar way than the previously described but adding
the required amount of tetraethylamonium hydroxide (TMAOH) together with the
quinolinium derivative hydroxide and seeds of pure silica LTA (10 of the total
inorganic oxides) in order to promote the crystallization The synthesis was
carried out at 135ordmC for 5 days The final composition is given in Table 1
The XRD pattern shows that Al-ITQ-29 was obtained with a small impurity of
RUB-10 The Al-MAS-NMR spectrum shows a single resonance at approx 55
ppm indicating the tetrahedral coordination of Al in the sample Also this
sample when calcined was able to interact with ammonia and acetonitrile
showing the accessibility of the acid sites for small molecules
13
II Chemical analyses and 13 C-CP-MAS-NMR spectroscopy characterization
results
The chemical compositions of the ITQ-29 samples described above are given in
Table 1
Table 1 Chemical compositions of ITQ-29 samples expressed as molar composition per unit cellSample Si
(uc)Ge (uc)
Al (uc)
C (uc)
N(uc)
F(uc)
OSDA(uc)
TMA(uc)
SR346B 164 76 --- 278 21 20 21(a) 0
SR386B 155 82 03 284 23 16 23(a) 0
SR408A 145 78 17 305 31 10 20(b) 10
SR455C 240 --- --- 282 30 20 18(b) 12
SR454A 207 21 12 312 30 12 21(b) 09
SR452B 235 --- 05 294 33 18 18(b) 15
(a) Calculated from the N content
(b) Calculated from the N and C contents and assuming no decomposition of
the OSDA
14
Figure 3a 13C-CP-MAS-NMR spectra of the as-prepared ITQ-29 zeolites indicates the spinning side bands
The 13C-NMR spectra indicate that the OSDA remains nearly intact within
the pores of the ITQ-29 zeolites as deduced from the close resemblance of the
solid NMR spectra and the liquid phase spectrum of an aqueous solution of the
OSDA In the spectra of the samples prepared in presence of TMAOH a new
signal at 58 ppm (marked as ) appears indicating that TMA+ cations are
incorporated into the solids Finally some minor decomposition products are
also detected (marked as )
15
4 Structure Refinement of SiGe-LTA and pure silica LTA
Structure refinement of Ge containing ITQ-29 sample (SiGe = 2)
The calcined sample with SiGe molar ratio of 21 was measured in
vacuum and the corresponding X ray powder diffraction (XRD) pattern is shown
in Figure 4a This pattern was also indexed according to a cubic unit cell with
refined cell parameter equal to 120157(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
According to the refined scattering power at the T site and assuming that it is
filled the unit cell composition of the calcined sample is Si166 Ge74 O48 ie the
refined SiGe ratio is 22 The averaged distance (d) and angles ( ) from the
tetrahedron are d(T-O)=162Aring (O-T-O) =1094ordm (T-O-T) = 1531ordm The
refined atomic coordinates are listed in Table 2 and Figure 4a shows the very
good agreement between observed and calculated XRD patterns The details of
the Rietveld refinement are given in the Experimental Section
Table 2 Fractional atomic coordinates[ab] for ITQ-29 (SiGe=22)
Atom x y z No of positions
Wyckoff notation
T[c] 03700(1) 01840(1) 0 24 k
O1 12 02118(5) 0 12 h
O2 02946(5) 02946(5) 0 12 i
O3 03370(3) 01095(4) 01095(4) 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=120157(4)Aring)[b] Estimated standard deviations given in parentheses[c] Refined atomic occupations for site T 069(2)Si+031(2)Ge
16
Figure 4a Observed (crosses) and calculated (lines) XRD patterns of ITQ-29 as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections The arrows indicate the tow small regions excluded from the Rietveld refinement containing the diffraction lines of the platinum sample holder (Cu K12 radiation)
Structure refinement of pure silica ITQ-29 sample
The purely siliceous sample was measured after calcination at 700ordmC
under air and the corresponding X ray powder diffraction (XRD) pattern is
shown in Figure 4b This pattern was indexed according to a cubic unit cell with
refined cell parameter equal to 118671(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
The refined atomic coordinates are given in Table 3 and Figure 4b shows the
very good agreement between observed and calculated XRD patterns which
confirms that ITQ-29 has LTA structure type
17
Table 3 Fractional atomic coordinates[ab] for pure silica ITQ-29
Atom x y z No of positions
Wyckoff notation
Si 03683(3) 01847(3) 0 24 k
O1 12 02179(7) 0 12 h
O2 02939(7) x 0 12 i
O3 03429(4) 01098(7) y 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=118671(4)Aring)[b] Estimated standard deviations given in parentheses
Figure 4b Observed (crosses) and calculated (lines) XRD patterns of pure silica zeolite A as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections (Cu K12 radiation) To emphasize the high angle portion of the pattern the first reflection has been cut at half height
The refined unit cell volume is shorter by 64 Aring3 than the volume found for
the Ge containing form (ie 1671 Aring3 in front of 1735 Aring3) This result is consistent
with the larger ionic radius of Ge compared to Si that is also responsible of the
larger averaged T-O distance obtained in the Ge zeolite (d(T-O)=162Aring) than in
18
the pure silica ITQ-29 material (d(Si-O)=160Aring) The averaged distance (d) and
angles ( ) from the tetrahedron are d(Si-O)=160Aring (O-Si-O) = 1094ordm (Si-
O-Si) = 1533ordm It is notorious (see Table 4) that the most tensioned Si-O-Si
angle is the Si-O2-Si angle (1584ordm) which correspond to the oxygen that is
linking to neighboured D4R cages On the other hand the Si-O-Si angles
corresponding to oxygen atoms placed at that small D4R cage do not seem to
be strongly constrained giving Si-O1-Si and Si-O3-Si angles of 1517 and
1497ordm respectively
Table 4 Bond distances in Aring and bond angles in (ordm) with esds in parentheses
for pure Si zeolite A
Si - O1 1612(5)Si - O2 1568(7)Si - O3 1606(7) (2x)O1 - Si - O2 1102(4)O1 - Si - O3 1085(5) (2x)O2 - Si - O3 1106(6) (2x)O3 - Si - O3 1085(7)Si - O1 -Si 1517(6)Si- O2 - Si 1584(9)Si - O3 - Si 1497(9)
The details of the Rietveld refinement are given in the Experimental Section
Experimental section
XRD
The Ge containing ITQ-29 sample was calcined at 700ordmC for 1 hour The
pattern was measured at room temperature in vacuum on a Philips XPert
diffractometer with Bragg-Brentano geometry using a Pt sample holder and an
19
XCelerator detector Intensity data obtained with fixed divergence slit (025ordm)
Cu K radiation ( = 15406 15444Aring) Tube voltage and intensity 45 kV and
40 mA Step size and time 0017ordm 2 and 6000s
The pure silica ITQ-29 sample was calcined at 700ordmC in air for 3 hours
The pattern was measured at room temperature on a Philips XPert
diffractometer with Bragg-Brentano geometry using a conventional flat stage
holder and an XCelerator detector Intensity data obtained with fixed
divergence slit (0125ordm) Cu K radiation ( = 15406 15444Aring) Tube voltage
and intensity 45 kV and 40 mA Step size and time 0017ordm 2 and 6000s
Rietveld refinement
The Rietveld refinement of Ge-ITQ-29 data was performed with LSP7
using a 2 range from 135ordm to 642ordm with the regions between 39344 - 40177
and 45701 - 47220 excluded due to the appearance in these regions of the
(111) and (200) Pt diffraction peaks of the sample holder The transmission
coefficient at the Pt(111) Bragg position is 035 which was used for correcting
the finite film thickness of the sample Number of contributing reflections is 86
No geometric restraints used Number of structural parameters is 7 Number of
profile parameters is 8 including unit cell parameters and zero shift (-0020ordm 2)
with visually estimated background (Average background = 38000 counts)
Profile function used was Pearson VII Refined overall thermal vibration
coefficient B = 60Aring2 The residuals of the refinement were Rwp=0026
Rp=0018 2=50
The Rietveld refinement of the pure silica-ITQ-29 data with LSP7 was
performed using the measured 2 range from 5ordm to 75ordm Number of contributing
20
reflections is 186 No geometric restraints used Number of structural
parameters is 7 Number of profile parameters is 8 including unit cell
parameters and zero shift (-0055ordm 2) with visually estimated background
(Average background = 400 counts) Profile function used was Pearson VII
Refined overall thermal vibration coefficient B = 07Aring2 The residuals of the
refinement were Rwp=0097 Rp=0062 RB=0032 2=28
21
5 Comparison of commercial LTA samples with ITQ-29 zeolites
The XRD patterns of different commercial LTA zeolites are given for
comparison purposes
Zeolite 3A is the potassium form of the LTA zeolite having the following
composition
06 K2O 040 Na2O 1 Al2O3 20 plusmn 01SiO2 x H2O
4A is the same zeolite but in the sodium its formula is
1 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
Finally 5A is the Ca2+ exchanged material with the following composition
080 CaO 020 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
(all of them were purchased from Aldrich Co)
As can be seen all the commercial LTA samples posses a framework SiAl ratio
close to 1
22
In the figure It can be seen there that the peak intensities greatly depend on the
nature of the exchanged cation located within the cavities of the LTA structure
Also the X-ray diffraction lines of pure silica ITQ-29 zeolite are shifted towards
low 2θ values (ie higher d spacing) due to the smaller ionic radii of Si than that
of Al However the formation of pure silica LTA can be unambiguously
confirmed from the absence of non assigned diffraction lines and the goodness
of Rietveld refinement
23
- SUPPLEMENTARY MATERIAL
-
C Photoluminiscence spectrum (ex=265 nm) of the 03 M OSDA aqueous
solution as hydroxide (This is the same concentration than that used for
the synthesis of ITQ-29) It is observed the presence of an intense
emission band at ca 450 nm The red-shift with respect to the monomer
spectrum has been attributed to the presence of π-stacking interactions
between adjacent aromatic rings (ref 16)
8
D Solid state Photoluminiscence spectrum (ex=265 nm) of the Iodide salt
of the OSDA It is seen that this spectrum is very similar to that obtained
in concentrated solution Since single crystal diffraction has shown that
the OSDA crystallised as dimers (see part 1 of this supplementary
material) we can unambiguously assigned the observed red-shift of the
emission to the π-stacking interactions between neighbored aromatic
rings Also the same interpretation could be valid for the most
concentrated aqueous solution (spectrum shown above)
9
300 400 500
80000
120000
160000
200000
Cou
nts
(au
)
Wavelength (nm)
E Solid state Photoluminiscence spectrum (ex=265 nm) of a ITQ-29 zeolite
(sample SR346b) in the as-prepared form
It is observed the presence of two emission bands at ca 310 and 430 nm
which were assigned to the OSDA as monomer and dimer respectively The
highest intensity of the second band indicates that most of the OSDA is
located inside of the ITQ-29 pores forming self-assembled dimers This is
further supported by chemical analyses and 13C-CP-MAS-NMR
spectroscopy (see supplementary material 3)
10
3 Synthesis and characterization of ITQ-29 zeolites
I Detailed synthesis methods
a) Al-free ITQ-29 (sample SR346B) was synthesized in fluoride media in the
presence of Ge from a gel of the following molar composition
067 SiO2 033 GeO2 05 ROH 05 HF 7 H2O
The gel was prepared by hydrolyzing tetraethylorthosilicate (TEOS) in an
aqueous solution of 4-methyl-2367-tetrahydro-1H5H-pyrido[321-ij]
quinolinium hydroxide (ROH) then the appropriate amount of GeO2 was added
and the mixture was kept under stirring until the ethanol formed upon hydrolysis
of TEOS and the appropriate excess of water were evaporated to reach the gel
composition given above Finally an aqueous solution of HF (50) was added
and the mixture was introduced in a Teflon-lined stainless autoclave and heated
at 150ordmC for 5 days
After this time the autoclave was cooled down and the mixture was
filtered washed with water and dried at 100ordmC The final composition is given in
Table 1 The zeolite was calcined at 700ordmC in air
b) Al-containing ITQ-29 (sample SR386B) was synthesized in fluoride media in
the presence of Ge from a gel of the following composition
067 SiO2 033 GeO2 002 Al2O3 05 ROH 05 HF 7 H2O
11
The gel preparation was similar to that described for the Al-free ITQ-29
with the addition of Al isopropoxide as the source of Al and seeds of ITQ-29
(5 of the total inorganic oxides) in order to promote the crystallization
The crystallization was also carried out at 150ordmC for 5 days The final
composition is given in Table 1
c) The high Al content ITQ-29 zeolite (sample SR408A) was synthesized using
a mixture of OSDAacutes the quinolinium derivative and tetramethylammonium It
was obtained from a gel of the following composition
067 SiO2 033 GeO2 007 Al2O3 025 ROH 025 TMAOH 05 HF 7 H2O
The gel was prepared in a similar way than the previously described but adding
the required amount of tetraethylamonium hydroxide (TAMOH) together with the
quinolinium derivative hydroxide and seeds (5 of the total inorganic oxides) in
order to promote the crystallization The synthesis was carried out at 150ordmC for
3 days The final composition is given in Table 1
d) Purely siliceous ITQ-29 (sample SR455C) was prepared in fluoride media
from a gel of the following composition
100 SiO2 025 ROH 025 TMAOH 05 HF 2 H2O
The gel was prepared as described for SR346B but the addition of GeO2
was skipped and the crystallization was done at 135ordmC for 7 days The final
composition is given in table 1 The zeolite obtained was calcined at 700ordmC in
air
12
e) The Al-ITQ-29 zeolite employed for the catalytic experiments (Sample
SR454A) was synthesized from a gel of the following composition
091 SiO2 009 GeO2 002 Al2O3 025 ROH 025 TMAOH 05 HF 3 H2O
The crystallization was performed at 135ordmC for 2 days The final composition is
given in Table 1
The zeolite was previously calcined at 580ordmC for 3 hours in air flow
before the catalytic experiments
f) Pure silicoaluminate ITQ-29 zeolite (sample SR452B) was synthesized using
a mixture of OSDAacutes the quinolinium derivative and tetramethylammonium It
was obtained from a gel of the following composition
100 SiO2 001 Al2O3 025 ROH 025 TMAOH 05 HF 3 H2O
The gel was prepared in a similar way than the previously described but adding
the required amount of tetraethylamonium hydroxide (TMAOH) together with the
quinolinium derivative hydroxide and seeds of pure silica LTA (10 of the total
inorganic oxides) in order to promote the crystallization The synthesis was
carried out at 135ordmC for 5 days The final composition is given in Table 1
The XRD pattern shows that Al-ITQ-29 was obtained with a small impurity of
RUB-10 The Al-MAS-NMR spectrum shows a single resonance at approx 55
ppm indicating the tetrahedral coordination of Al in the sample Also this
sample when calcined was able to interact with ammonia and acetonitrile
showing the accessibility of the acid sites for small molecules
13
II Chemical analyses and 13 C-CP-MAS-NMR spectroscopy characterization
results
The chemical compositions of the ITQ-29 samples described above are given in
Table 1
Table 1 Chemical compositions of ITQ-29 samples expressed as molar composition per unit cellSample Si
(uc)Ge (uc)
Al (uc)
C (uc)
N(uc)
F(uc)
OSDA(uc)
TMA(uc)
SR346B 164 76 --- 278 21 20 21(a) 0
SR386B 155 82 03 284 23 16 23(a) 0
SR408A 145 78 17 305 31 10 20(b) 10
SR455C 240 --- --- 282 30 20 18(b) 12
SR454A 207 21 12 312 30 12 21(b) 09
SR452B 235 --- 05 294 33 18 18(b) 15
(a) Calculated from the N content
(b) Calculated from the N and C contents and assuming no decomposition of
the OSDA
14
Figure 3a 13C-CP-MAS-NMR spectra of the as-prepared ITQ-29 zeolites indicates the spinning side bands
The 13C-NMR spectra indicate that the OSDA remains nearly intact within
the pores of the ITQ-29 zeolites as deduced from the close resemblance of the
solid NMR spectra and the liquid phase spectrum of an aqueous solution of the
OSDA In the spectra of the samples prepared in presence of TMAOH a new
signal at 58 ppm (marked as ) appears indicating that TMA+ cations are
incorporated into the solids Finally some minor decomposition products are
also detected (marked as )
15
4 Structure Refinement of SiGe-LTA and pure silica LTA
Structure refinement of Ge containing ITQ-29 sample (SiGe = 2)
The calcined sample with SiGe molar ratio of 21 was measured in
vacuum and the corresponding X ray powder diffraction (XRD) pattern is shown
in Figure 4a This pattern was also indexed according to a cubic unit cell with
refined cell parameter equal to 120157(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
According to the refined scattering power at the T site and assuming that it is
filled the unit cell composition of the calcined sample is Si166 Ge74 O48 ie the
refined SiGe ratio is 22 The averaged distance (d) and angles ( ) from the
tetrahedron are d(T-O)=162Aring (O-T-O) =1094ordm (T-O-T) = 1531ordm The
refined atomic coordinates are listed in Table 2 and Figure 4a shows the very
good agreement between observed and calculated XRD patterns The details of
the Rietveld refinement are given in the Experimental Section
Table 2 Fractional atomic coordinates[ab] for ITQ-29 (SiGe=22)
Atom x y z No of positions
Wyckoff notation
T[c] 03700(1) 01840(1) 0 24 k
O1 12 02118(5) 0 12 h
O2 02946(5) 02946(5) 0 12 i
O3 03370(3) 01095(4) 01095(4) 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=120157(4)Aring)[b] Estimated standard deviations given in parentheses[c] Refined atomic occupations for site T 069(2)Si+031(2)Ge
16
Figure 4a Observed (crosses) and calculated (lines) XRD patterns of ITQ-29 as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections The arrows indicate the tow small regions excluded from the Rietveld refinement containing the diffraction lines of the platinum sample holder (Cu K12 radiation)
Structure refinement of pure silica ITQ-29 sample
The purely siliceous sample was measured after calcination at 700ordmC
under air and the corresponding X ray powder diffraction (XRD) pattern is
shown in Figure 4b This pattern was indexed according to a cubic unit cell with
refined cell parameter equal to 118671(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
The refined atomic coordinates are given in Table 3 and Figure 4b shows the
very good agreement between observed and calculated XRD patterns which
confirms that ITQ-29 has LTA structure type
17
Table 3 Fractional atomic coordinates[ab] for pure silica ITQ-29
Atom x y z No of positions
Wyckoff notation
Si 03683(3) 01847(3) 0 24 k
O1 12 02179(7) 0 12 h
O2 02939(7) x 0 12 i
O3 03429(4) 01098(7) y 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=118671(4)Aring)[b] Estimated standard deviations given in parentheses
Figure 4b Observed (crosses) and calculated (lines) XRD patterns of pure silica zeolite A as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections (Cu K12 radiation) To emphasize the high angle portion of the pattern the first reflection has been cut at half height
The refined unit cell volume is shorter by 64 Aring3 than the volume found for
the Ge containing form (ie 1671 Aring3 in front of 1735 Aring3) This result is consistent
with the larger ionic radius of Ge compared to Si that is also responsible of the
larger averaged T-O distance obtained in the Ge zeolite (d(T-O)=162Aring) than in
18
the pure silica ITQ-29 material (d(Si-O)=160Aring) The averaged distance (d) and
angles ( ) from the tetrahedron are d(Si-O)=160Aring (O-Si-O) = 1094ordm (Si-
O-Si) = 1533ordm It is notorious (see Table 4) that the most tensioned Si-O-Si
angle is the Si-O2-Si angle (1584ordm) which correspond to the oxygen that is
linking to neighboured D4R cages On the other hand the Si-O-Si angles
corresponding to oxygen atoms placed at that small D4R cage do not seem to
be strongly constrained giving Si-O1-Si and Si-O3-Si angles of 1517 and
1497ordm respectively
Table 4 Bond distances in Aring and bond angles in (ordm) with esds in parentheses
for pure Si zeolite A
Si - O1 1612(5)Si - O2 1568(7)Si - O3 1606(7) (2x)O1 - Si - O2 1102(4)O1 - Si - O3 1085(5) (2x)O2 - Si - O3 1106(6) (2x)O3 - Si - O3 1085(7)Si - O1 -Si 1517(6)Si- O2 - Si 1584(9)Si - O3 - Si 1497(9)
The details of the Rietveld refinement are given in the Experimental Section
Experimental section
XRD
The Ge containing ITQ-29 sample was calcined at 700ordmC for 1 hour The
pattern was measured at room temperature in vacuum on a Philips XPert
diffractometer with Bragg-Brentano geometry using a Pt sample holder and an
19
XCelerator detector Intensity data obtained with fixed divergence slit (025ordm)
Cu K radiation ( = 15406 15444Aring) Tube voltage and intensity 45 kV and
40 mA Step size and time 0017ordm 2 and 6000s
The pure silica ITQ-29 sample was calcined at 700ordmC in air for 3 hours
The pattern was measured at room temperature on a Philips XPert
diffractometer with Bragg-Brentano geometry using a conventional flat stage
holder and an XCelerator detector Intensity data obtained with fixed
divergence slit (0125ordm) Cu K radiation ( = 15406 15444Aring) Tube voltage
and intensity 45 kV and 40 mA Step size and time 0017ordm 2 and 6000s
Rietveld refinement
The Rietveld refinement of Ge-ITQ-29 data was performed with LSP7
using a 2 range from 135ordm to 642ordm with the regions between 39344 - 40177
and 45701 - 47220 excluded due to the appearance in these regions of the
(111) and (200) Pt diffraction peaks of the sample holder The transmission
coefficient at the Pt(111) Bragg position is 035 which was used for correcting
the finite film thickness of the sample Number of contributing reflections is 86
No geometric restraints used Number of structural parameters is 7 Number of
profile parameters is 8 including unit cell parameters and zero shift (-0020ordm 2)
with visually estimated background (Average background = 38000 counts)
Profile function used was Pearson VII Refined overall thermal vibration
coefficient B = 60Aring2 The residuals of the refinement were Rwp=0026
Rp=0018 2=50
The Rietveld refinement of the pure silica-ITQ-29 data with LSP7 was
performed using the measured 2 range from 5ordm to 75ordm Number of contributing
20
reflections is 186 No geometric restraints used Number of structural
parameters is 7 Number of profile parameters is 8 including unit cell
parameters and zero shift (-0055ordm 2) with visually estimated background
(Average background = 400 counts) Profile function used was Pearson VII
Refined overall thermal vibration coefficient B = 07Aring2 The residuals of the
refinement were Rwp=0097 Rp=0062 RB=0032 2=28
21
5 Comparison of commercial LTA samples with ITQ-29 zeolites
The XRD patterns of different commercial LTA zeolites are given for
comparison purposes
Zeolite 3A is the potassium form of the LTA zeolite having the following
composition
06 K2O 040 Na2O 1 Al2O3 20 plusmn 01SiO2 x H2O
4A is the same zeolite but in the sodium its formula is
1 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
Finally 5A is the Ca2+ exchanged material with the following composition
080 CaO 020 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
(all of them were purchased from Aldrich Co)
As can be seen all the commercial LTA samples posses a framework SiAl ratio
close to 1
22
In the figure It can be seen there that the peak intensities greatly depend on the
nature of the exchanged cation located within the cavities of the LTA structure
Also the X-ray diffraction lines of pure silica ITQ-29 zeolite are shifted towards
low 2θ values (ie higher d spacing) due to the smaller ionic radii of Si than that
of Al However the formation of pure silica LTA can be unambiguously
confirmed from the absence of non assigned diffraction lines and the goodness
of Rietveld refinement
23
- SUPPLEMENTARY MATERIAL
-
D Solid state Photoluminiscence spectrum (ex=265 nm) of the Iodide salt
of the OSDA It is seen that this spectrum is very similar to that obtained
in concentrated solution Since single crystal diffraction has shown that
the OSDA crystallised as dimers (see part 1 of this supplementary
material) we can unambiguously assigned the observed red-shift of the
emission to the π-stacking interactions between neighbored aromatic
rings Also the same interpretation could be valid for the most
concentrated aqueous solution (spectrum shown above)
9
300 400 500
80000
120000
160000
200000
Cou
nts
(au
)
Wavelength (nm)
E Solid state Photoluminiscence spectrum (ex=265 nm) of a ITQ-29 zeolite
(sample SR346b) in the as-prepared form
It is observed the presence of two emission bands at ca 310 and 430 nm
which were assigned to the OSDA as monomer and dimer respectively The
highest intensity of the second band indicates that most of the OSDA is
located inside of the ITQ-29 pores forming self-assembled dimers This is
further supported by chemical analyses and 13C-CP-MAS-NMR
spectroscopy (see supplementary material 3)
10
3 Synthesis and characterization of ITQ-29 zeolites
I Detailed synthesis methods
a) Al-free ITQ-29 (sample SR346B) was synthesized in fluoride media in the
presence of Ge from a gel of the following molar composition
067 SiO2 033 GeO2 05 ROH 05 HF 7 H2O
The gel was prepared by hydrolyzing tetraethylorthosilicate (TEOS) in an
aqueous solution of 4-methyl-2367-tetrahydro-1H5H-pyrido[321-ij]
quinolinium hydroxide (ROH) then the appropriate amount of GeO2 was added
and the mixture was kept under stirring until the ethanol formed upon hydrolysis
of TEOS and the appropriate excess of water were evaporated to reach the gel
composition given above Finally an aqueous solution of HF (50) was added
and the mixture was introduced in a Teflon-lined stainless autoclave and heated
at 150ordmC for 5 days
After this time the autoclave was cooled down and the mixture was
filtered washed with water and dried at 100ordmC The final composition is given in
Table 1 The zeolite was calcined at 700ordmC in air
b) Al-containing ITQ-29 (sample SR386B) was synthesized in fluoride media in
the presence of Ge from a gel of the following composition
067 SiO2 033 GeO2 002 Al2O3 05 ROH 05 HF 7 H2O
11
The gel preparation was similar to that described for the Al-free ITQ-29
with the addition of Al isopropoxide as the source of Al and seeds of ITQ-29
(5 of the total inorganic oxides) in order to promote the crystallization
The crystallization was also carried out at 150ordmC for 5 days The final
composition is given in Table 1
c) The high Al content ITQ-29 zeolite (sample SR408A) was synthesized using
a mixture of OSDAacutes the quinolinium derivative and tetramethylammonium It
was obtained from a gel of the following composition
067 SiO2 033 GeO2 007 Al2O3 025 ROH 025 TMAOH 05 HF 7 H2O
The gel was prepared in a similar way than the previously described but adding
the required amount of tetraethylamonium hydroxide (TAMOH) together with the
quinolinium derivative hydroxide and seeds (5 of the total inorganic oxides) in
order to promote the crystallization The synthesis was carried out at 150ordmC for
3 days The final composition is given in Table 1
d) Purely siliceous ITQ-29 (sample SR455C) was prepared in fluoride media
from a gel of the following composition
100 SiO2 025 ROH 025 TMAOH 05 HF 2 H2O
The gel was prepared as described for SR346B but the addition of GeO2
was skipped and the crystallization was done at 135ordmC for 7 days The final
composition is given in table 1 The zeolite obtained was calcined at 700ordmC in
air
12
e) The Al-ITQ-29 zeolite employed for the catalytic experiments (Sample
SR454A) was synthesized from a gel of the following composition
091 SiO2 009 GeO2 002 Al2O3 025 ROH 025 TMAOH 05 HF 3 H2O
The crystallization was performed at 135ordmC for 2 days The final composition is
given in Table 1
The zeolite was previously calcined at 580ordmC for 3 hours in air flow
before the catalytic experiments
f) Pure silicoaluminate ITQ-29 zeolite (sample SR452B) was synthesized using
a mixture of OSDAacutes the quinolinium derivative and tetramethylammonium It
was obtained from a gel of the following composition
100 SiO2 001 Al2O3 025 ROH 025 TMAOH 05 HF 3 H2O
The gel was prepared in a similar way than the previously described but adding
the required amount of tetraethylamonium hydroxide (TMAOH) together with the
quinolinium derivative hydroxide and seeds of pure silica LTA (10 of the total
inorganic oxides) in order to promote the crystallization The synthesis was
carried out at 135ordmC for 5 days The final composition is given in Table 1
The XRD pattern shows that Al-ITQ-29 was obtained with a small impurity of
RUB-10 The Al-MAS-NMR spectrum shows a single resonance at approx 55
ppm indicating the tetrahedral coordination of Al in the sample Also this
sample when calcined was able to interact with ammonia and acetonitrile
showing the accessibility of the acid sites for small molecules
13
II Chemical analyses and 13 C-CP-MAS-NMR spectroscopy characterization
results
The chemical compositions of the ITQ-29 samples described above are given in
Table 1
Table 1 Chemical compositions of ITQ-29 samples expressed as molar composition per unit cellSample Si
(uc)Ge (uc)
Al (uc)
C (uc)
N(uc)
F(uc)
OSDA(uc)
TMA(uc)
SR346B 164 76 --- 278 21 20 21(a) 0
SR386B 155 82 03 284 23 16 23(a) 0
SR408A 145 78 17 305 31 10 20(b) 10
SR455C 240 --- --- 282 30 20 18(b) 12
SR454A 207 21 12 312 30 12 21(b) 09
SR452B 235 --- 05 294 33 18 18(b) 15
(a) Calculated from the N content
(b) Calculated from the N and C contents and assuming no decomposition of
the OSDA
14
Figure 3a 13C-CP-MAS-NMR spectra of the as-prepared ITQ-29 zeolites indicates the spinning side bands
The 13C-NMR spectra indicate that the OSDA remains nearly intact within
the pores of the ITQ-29 zeolites as deduced from the close resemblance of the
solid NMR spectra and the liquid phase spectrum of an aqueous solution of the
OSDA In the spectra of the samples prepared in presence of TMAOH a new
signal at 58 ppm (marked as ) appears indicating that TMA+ cations are
incorporated into the solids Finally some minor decomposition products are
also detected (marked as )
15
4 Structure Refinement of SiGe-LTA and pure silica LTA
Structure refinement of Ge containing ITQ-29 sample (SiGe = 2)
The calcined sample with SiGe molar ratio of 21 was measured in
vacuum and the corresponding X ray powder diffraction (XRD) pattern is shown
in Figure 4a This pattern was also indexed according to a cubic unit cell with
refined cell parameter equal to 120157(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
According to the refined scattering power at the T site and assuming that it is
filled the unit cell composition of the calcined sample is Si166 Ge74 O48 ie the
refined SiGe ratio is 22 The averaged distance (d) and angles ( ) from the
tetrahedron are d(T-O)=162Aring (O-T-O) =1094ordm (T-O-T) = 1531ordm The
refined atomic coordinates are listed in Table 2 and Figure 4a shows the very
good agreement between observed and calculated XRD patterns The details of
the Rietveld refinement are given in the Experimental Section
Table 2 Fractional atomic coordinates[ab] for ITQ-29 (SiGe=22)
Atom x y z No of positions
Wyckoff notation
T[c] 03700(1) 01840(1) 0 24 k
O1 12 02118(5) 0 12 h
O2 02946(5) 02946(5) 0 12 i
O3 03370(3) 01095(4) 01095(4) 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=120157(4)Aring)[b] Estimated standard deviations given in parentheses[c] Refined atomic occupations for site T 069(2)Si+031(2)Ge
16
Figure 4a Observed (crosses) and calculated (lines) XRD patterns of ITQ-29 as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections The arrows indicate the tow small regions excluded from the Rietveld refinement containing the diffraction lines of the platinum sample holder (Cu K12 radiation)
Structure refinement of pure silica ITQ-29 sample
The purely siliceous sample was measured after calcination at 700ordmC
under air and the corresponding X ray powder diffraction (XRD) pattern is
shown in Figure 4b This pattern was indexed according to a cubic unit cell with
refined cell parameter equal to 118671(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
The refined atomic coordinates are given in Table 3 and Figure 4b shows the
very good agreement between observed and calculated XRD patterns which
confirms that ITQ-29 has LTA structure type
17
Table 3 Fractional atomic coordinates[ab] for pure silica ITQ-29
Atom x y z No of positions
Wyckoff notation
Si 03683(3) 01847(3) 0 24 k
O1 12 02179(7) 0 12 h
O2 02939(7) x 0 12 i
O3 03429(4) 01098(7) y 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=118671(4)Aring)[b] Estimated standard deviations given in parentheses
Figure 4b Observed (crosses) and calculated (lines) XRD patterns of pure silica zeolite A as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections (Cu K12 radiation) To emphasize the high angle portion of the pattern the first reflection has been cut at half height
The refined unit cell volume is shorter by 64 Aring3 than the volume found for
the Ge containing form (ie 1671 Aring3 in front of 1735 Aring3) This result is consistent
with the larger ionic radius of Ge compared to Si that is also responsible of the
larger averaged T-O distance obtained in the Ge zeolite (d(T-O)=162Aring) than in
18
the pure silica ITQ-29 material (d(Si-O)=160Aring) The averaged distance (d) and
angles ( ) from the tetrahedron are d(Si-O)=160Aring (O-Si-O) = 1094ordm (Si-
O-Si) = 1533ordm It is notorious (see Table 4) that the most tensioned Si-O-Si
angle is the Si-O2-Si angle (1584ordm) which correspond to the oxygen that is
linking to neighboured D4R cages On the other hand the Si-O-Si angles
corresponding to oxygen atoms placed at that small D4R cage do not seem to
be strongly constrained giving Si-O1-Si and Si-O3-Si angles of 1517 and
1497ordm respectively
Table 4 Bond distances in Aring and bond angles in (ordm) with esds in parentheses
for pure Si zeolite A
Si - O1 1612(5)Si - O2 1568(7)Si - O3 1606(7) (2x)O1 - Si - O2 1102(4)O1 - Si - O3 1085(5) (2x)O2 - Si - O3 1106(6) (2x)O3 - Si - O3 1085(7)Si - O1 -Si 1517(6)Si- O2 - Si 1584(9)Si - O3 - Si 1497(9)
The details of the Rietveld refinement are given in the Experimental Section
Experimental section
XRD
The Ge containing ITQ-29 sample was calcined at 700ordmC for 1 hour The
pattern was measured at room temperature in vacuum on a Philips XPert
diffractometer with Bragg-Brentano geometry using a Pt sample holder and an
19
XCelerator detector Intensity data obtained with fixed divergence slit (025ordm)
Cu K radiation ( = 15406 15444Aring) Tube voltage and intensity 45 kV and
40 mA Step size and time 0017ordm 2 and 6000s
The pure silica ITQ-29 sample was calcined at 700ordmC in air for 3 hours
The pattern was measured at room temperature on a Philips XPert
diffractometer with Bragg-Brentano geometry using a conventional flat stage
holder and an XCelerator detector Intensity data obtained with fixed
divergence slit (0125ordm) Cu K radiation ( = 15406 15444Aring) Tube voltage
and intensity 45 kV and 40 mA Step size and time 0017ordm 2 and 6000s
Rietveld refinement
The Rietveld refinement of Ge-ITQ-29 data was performed with LSP7
using a 2 range from 135ordm to 642ordm with the regions between 39344 - 40177
and 45701 - 47220 excluded due to the appearance in these regions of the
(111) and (200) Pt diffraction peaks of the sample holder The transmission
coefficient at the Pt(111) Bragg position is 035 which was used for correcting
the finite film thickness of the sample Number of contributing reflections is 86
No geometric restraints used Number of structural parameters is 7 Number of
profile parameters is 8 including unit cell parameters and zero shift (-0020ordm 2)
with visually estimated background (Average background = 38000 counts)
Profile function used was Pearson VII Refined overall thermal vibration
coefficient B = 60Aring2 The residuals of the refinement were Rwp=0026
Rp=0018 2=50
The Rietveld refinement of the pure silica-ITQ-29 data with LSP7 was
performed using the measured 2 range from 5ordm to 75ordm Number of contributing
20
reflections is 186 No geometric restraints used Number of structural
parameters is 7 Number of profile parameters is 8 including unit cell
parameters and zero shift (-0055ordm 2) with visually estimated background
(Average background = 400 counts) Profile function used was Pearson VII
Refined overall thermal vibration coefficient B = 07Aring2 The residuals of the
refinement were Rwp=0097 Rp=0062 RB=0032 2=28
21
5 Comparison of commercial LTA samples with ITQ-29 zeolites
The XRD patterns of different commercial LTA zeolites are given for
comparison purposes
Zeolite 3A is the potassium form of the LTA zeolite having the following
composition
06 K2O 040 Na2O 1 Al2O3 20 plusmn 01SiO2 x H2O
4A is the same zeolite but in the sodium its formula is
1 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
Finally 5A is the Ca2+ exchanged material with the following composition
080 CaO 020 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
(all of them were purchased from Aldrich Co)
As can be seen all the commercial LTA samples posses a framework SiAl ratio
close to 1
22
In the figure It can be seen there that the peak intensities greatly depend on the
nature of the exchanged cation located within the cavities of the LTA structure
Also the X-ray diffraction lines of pure silica ITQ-29 zeolite are shifted towards
low 2θ values (ie higher d spacing) due to the smaller ionic radii of Si than that
of Al However the formation of pure silica LTA can be unambiguously
confirmed from the absence of non assigned diffraction lines and the goodness
of Rietveld refinement
23
- SUPPLEMENTARY MATERIAL
-
E Solid state Photoluminiscence spectrum (ex=265 nm) of a ITQ-29 zeolite
(sample SR346b) in the as-prepared form
It is observed the presence of two emission bands at ca 310 and 430 nm
which were assigned to the OSDA as monomer and dimer respectively The
highest intensity of the second band indicates that most of the OSDA is
located inside of the ITQ-29 pores forming self-assembled dimers This is
further supported by chemical analyses and 13C-CP-MAS-NMR
spectroscopy (see supplementary material 3)
10
3 Synthesis and characterization of ITQ-29 zeolites
I Detailed synthesis methods
a) Al-free ITQ-29 (sample SR346B) was synthesized in fluoride media in the
presence of Ge from a gel of the following molar composition
067 SiO2 033 GeO2 05 ROH 05 HF 7 H2O
The gel was prepared by hydrolyzing tetraethylorthosilicate (TEOS) in an
aqueous solution of 4-methyl-2367-tetrahydro-1H5H-pyrido[321-ij]
quinolinium hydroxide (ROH) then the appropriate amount of GeO2 was added
and the mixture was kept under stirring until the ethanol formed upon hydrolysis
of TEOS and the appropriate excess of water were evaporated to reach the gel
composition given above Finally an aqueous solution of HF (50) was added
and the mixture was introduced in a Teflon-lined stainless autoclave and heated
at 150ordmC for 5 days
After this time the autoclave was cooled down and the mixture was
filtered washed with water and dried at 100ordmC The final composition is given in
Table 1 The zeolite was calcined at 700ordmC in air
b) Al-containing ITQ-29 (sample SR386B) was synthesized in fluoride media in
the presence of Ge from a gel of the following composition
067 SiO2 033 GeO2 002 Al2O3 05 ROH 05 HF 7 H2O
11
The gel preparation was similar to that described for the Al-free ITQ-29
with the addition of Al isopropoxide as the source of Al and seeds of ITQ-29
(5 of the total inorganic oxides) in order to promote the crystallization
The crystallization was also carried out at 150ordmC for 5 days The final
composition is given in Table 1
c) The high Al content ITQ-29 zeolite (sample SR408A) was synthesized using
a mixture of OSDAacutes the quinolinium derivative and tetramethylammonium It
was obtained from a gel of the following composition
067 SiO2 033 GeO2 007 Al2O3 025 ROH 025 TMAOH 05 HF 7 H2O
The gel was prepared in a similar way than the previously described but adding
the required amount of tetraethylamonium hydroxide (TAMOH) together with the
quinolinium derivative hydroxide and seeds (5 of the total inorganic oxides) in
order to promote the crystallization The synthesis was carried out at 150ordmC for
3 days The final composition is given in Table 1
d) Purely siliceous ITQ-29 (sample SR455C) was prepared in fluoride media
from a gel of the following composition
100 SiO2 025 ROH 025 TMAOH 05 HF 2 H2O
The gel was prepared as described for SR346B but the addition of GeO2
was skipped and the crystallization was done at 135ordmC for 7 days The final
composition is given in table 1 The zeolite obtained was calcined at 700ordmC in
air
12
e) The Al-ITQ-29 zeolite employed for the catalytic experiments (Sample
SR454A) was synthesized from a gel of the following composition
091 SiO2 009 GeO2 002 Al2O3 025 ROH 025 TMAOH 05 HF 3 H2O
The crystallization was performed at 135ordmC for 2 days The final composition is
given in Table 1
The zeolite was previously calcined at 580ordmC for 3 hours in air flow
before the catalytic experiments
f) Pure silicoaluminate ITQ-29 zeolite (sample SR452B) was synthesized using
a mixture of OSDAacutes the quinolinium derivative and tetramethylammonium It
was obtained from a gel of the following composition
100 SiO2 001 Al2O3 025 ROH 025 TMAOH 05 HF 3 H2O
The gel was prepared in a similar way than the previously described but adding
the required amount of tetraethylamonium hydroxide (TMAOH) together with the
quinolinium derivative hydroxide and seeds of pure silica LTA (10 of the total
inorganic oxides) in order to promote the crystallization The synthesis was
carried out at 135ordmC for 5 days The final composition is given in Table 1
The XRD pattern shows that Al-ITQ-29 was obtained with a small impurity of
RUB-10 The Al-MAS-NMR spectrum shows a single resonance at approx 55
ppm indicating the tetrahedral coordination of Al in the sample Also this
sample when calcined was able to interact with ammonia and acetonitrile
showing the accessibility of the acid sites for small molecules
13
II Chemical analyses and 13 C-CP-MAS-NMR spectroscopy characterization
results
The chemical compositions of the ITQ-29 samples described above are given in
Table 1
Table 1 Chemical compositions of ITQ-29 samples expressed as molar composition per unit cellSample Si
(uc)Ge (uc)
Al (uc)
C (uc)
N(uc)
F(uc)
OSDA(uc)
TMA(uc)
SR346B 164 76 --- 278 21 20 21(a) 0
SR386B 155 82 03 284 23 16 23(a) 0
SR408A 145 78 17 305 31 10 20(b) 10
SR455C 240 --- --- 282 30 20 18(b) 12
SR454A 207 21 12 312 30 12 21(b) 09
SR452B 235 --- 05 294 33 18 18(b) 15
(a) Calculated from the N content
(b) Calculated from the N and C contents and assuming no decomposition of
the OSDA
14
Figure 3a 13C-CP-MAS-NMR spectra of the as-prepared ITQ-29 zeolites indicates the spinning side bands
The 13C-NMR spectra indicate that the OSDA remains nearly intact within
the pores of the ITQ-29 zeolites as deduced from the close resemblance of the
solid NMR spectra and the liquid phase spectrum of an aqueous solution of the
OSDA In the spectra of the samples prepared in presence of TMAOH a new
signal at 58 ppm (marked as ) appears indicating that TMA+ cations are
incorporated into the solids Finally some minor decomposition products are
also detected (marked as )
15
4 Structure Refinement of SiGe-LTA and pure silica LTA
Structure refinement of Ge containing ITQ-29 sample (SiGe = 2)
The calcined sample with SiGe molar ratio of 21 was measured in
vacuum and the corresponding X ray powder diffraction (XRD) pattern is shown
in Figure 4a This pattern was also indexed according to a cubic unit cell with
refined cell parameter equal to 120157(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
According to the refined scattering power at the T site and assuming that it is
filled the unit cell composition of the calcined sample is Si166 Ge74 O48 ie the
refined SiGe ratio is 22 The averaged distance (d) and angles ( ) from the
tetrahedron are d(T-O)=162Aring (O-T-O) =1094ordm (T-O-T) = 1531ordm The
refined atomic coordinates are listed in Table 2 and Figure 4a shows the very
good agreement between observed and calculated XRD patterns The details of
the Rietveld refinement are given in the Experimental Section
Table 2 Fractional atomic coordinates[ab] for ITQ-29 (SiGe=22)
Atom x y z No of positions
Wyckoff notation
T[c] 03700(1) 01840(1) 0 24 k
O1 12 02118(5) 0 12 h
O2 02946(5) 02946(5) 0 12 i
O3 03370(3) 01095(4) 01095(4) 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=120157(4)Aring)[b] Estimated standard deviations given in parentheses[c] Refined atomic occupations for site T 069(2)Si+031(2)Ge
16
Figure 4a Observed (crosses) and calculated (lines) XRD patterns of ITQ-29 as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections The arrows indicate the tow small regions excluded from the Rietveld refinement containing the diffraction lines of the platinum sample holder (Cu K12 radiation)
Structure refinement of pure silica ITQ-29 sample
The purely siliceous sample was measured after calcination at 700ordmC
under air and the corresponding X ray powder diffraction (XRD) pattern is
shown in Figure 4b This pattern was indexed according to a cubic unit cell with
refined cell parameter equal to 118671(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
The refined atomic coordinates are given in Table 3 and Figure 4b shows the
very good agreement between observed and calculated XRD patterns which
confirms that ITQ-29 has LTA structure type
17
Table 3 Fractional atomic coordinates[ab] for pure silica ITQ-29
Atom x y z No of positions
Wyckoff notation
Si 03683(3) 01847(3) 0 24 k
O1 12 02179(7) 0 12 h
O2 02939(7) x 0 12 i
O3 03429(4) 01098(7) y 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=118671(4)Aring)[b] Estimated standard deviations given in parentheses
Figure 4b Observed (crosses) and calculated (lines) XRD patterns of pure silica zeolite A as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections (Cu K12 radiation) To emphasize the high angle portion of the pattern the first reflection has been cut at half height
The refined unit cell volume is shorter by 64 Aring3 than the volume found for
the Ge containing form (ie 1671 Aring3 in front of 1735 Aring3) This result is consistent
with the larger ionic radius of Ge compared to Si that is also responsible of the
larger averaged T-O distance obtained in the Ge zeolite (d(T-O)=162Aring) than in
18
the pure silica ITQ-29 material (d(Si-O)=160Aring) The averaged distance (d) and
angles ( ) from the tetrahedron are d(Si-O)=160Aring (O-Si-O) = 1094ordm (Si-
O-Si) = 1533ordm It is notorious (see Table 4) that the most tensioned Si-O-Si
angle is the Si-O2-Si angle (1584ordm) which correspond to the oxygen that is
linking to neighboured D4R cages On the other hand the Si-O-Si angles
corresponding to oxygen atoms placed at that small D4R cage do not seem to
be strongly constrained giving Si-O1-Si and Si-O3-Si angles of 1517 and
1497ordm respectively
Table 4 Bond distances in Aring and bond angles in (ordm) with esds in parentheses
for pure Si zeolite A
Si - O1 1612(5)Si - O2 1568(7)Si - O3 1606(7) (2x)O1 - Si - O2 1102(4)O1 - Si - O3 1085(5) (2x)O2 - Si - O3 1106(6) (2x)O3 - Si - O3 1085(7)Si - O1 -Si 1517(6)Si- O2 - Si 1584(9)Si - O3 - Si 1497(9)
The details of the Rietveld refinement are given in the Experimental Section
Experimental section
XRD
The Ge containing ITQ-29 sample was calcined at 700ordmC for 1 hour The
pattern was measured at room temperature in vacuum on a Philips XPert
diffractometer with Bragg-Brentano geometry using a Pt sample holder and an
19
XCelerator detector Intensity data obtained with fixed divergence slit (025ordm)
Cu K radiation ( = 15406 15444Aring) Tube voltage and intensity 45 kV and
40 mA Step size and time 0017ordm 2 and 6000s
The pure silica ITQ-29 sample was calcined at 700ordmC in air for 3 hours
The pattern was measured at room temperature on a Philips XPert
diffractometer with Bragg-Brentano geometry using a conventional flat stage
holder and an XCelerator detector Intensity data obtained with fixed
divergence slit (0125ordm) Cu K radiation ( = 15406 15444Aring) Tube voltage
and intensity 45 kV and 40 mA Step size and time 0017ordm 2 and 6000s
Rietveld refinement
The Rietveld refinement of Ge-ITQ-29 data was performed with LSP7
using a 2 range from 135ordm to 642ordm with the regions between 39344 - 40177
and 45701 - 47220 excluded due to the appearance in these regions of the
(111) and (200) Pt diffraction peaks of the sample holder The transmission
coefficient at the Pt(111) Bragg position is 035 which was used for correcting
the finite film thickness of the sample Number of contributing reflections is 86
No geometric restraints used Number of structural parameters is 7 Number of
profile parameters is 8 including unit cell parameters and zero shift (-0020ordm 2)
with visually estimated background (Average background = 38000 counts)
Profile function used was Pearson VII Refined overall thermal vibration
coefficient B = 60Aring2 The residuals of the refinement were Rwp=0026
Rp=0018 2=50
The Rietveld refinement of the pure silica-ITQ-29 data with LSP7 was
performed using the measured 2 range from 5ordm to 75ordm Number of contributing
20
reflections is 186 No geometric restraints used Number of structural
parameters is 7 Number of profile parameters is 8 including unit cell
parameters and zero shift (-0055ordm 2) with visually estimated background
(Average background = 400 counts) Profile function used was Pearson VII
Refined overall thermal vibration coefficient B = 07Aring2 The residuals of the
refinement were Rwp=0097 Rp=0062 RB=0032 2=28
21
5 Comparison of commercial LTA samples with ITQ-29 zeolites
The XRD patterns of different commercial LTA zeolites are given for
comparison purposes
Zeolite 3A is the potassium form of the LTA zeolite having the following
composition
06 K2O 040 Na2O 1 Al2O3 20 plusmn 01SiO2 x H2O
4A is the same zeolite but in the sodium its formula is
1 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
Finally 5A is the Ca2+ exchanged material with the following composition
080 CaO 020 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
(all of them were purchased from Aldrich Co)
As can be seen all the commercial LTA samples posses a framework SiAl ratio
close to 1
22
In the figure It can be seen there that the peak intensities greatly depend on the
nature of the exchanged cation located within the cavities of the LTA structure
Also the X-ray diffraction lines of pure silica ITQ-29 zeolite are shifted towards
low 2θ values (ie higher d spacing) due to the smaller ionic radii of Si than that
of Al However the formation of pure silica LTA can be unambiguously
confirmed from the absence of non assigned diffraction lines and the goodness
of Rietveld refinement
23
- SUPPLEMENTARY MATERIAL
-
3 Synthesis and characterization of ITQ-29 zeolites
I Detailed synthesis methods
a) Al-free ITQ-29 (sample SR346B) was synthesized in fluoride media in the
presence of Ge from a gel of the following molar composition
067 SiO2 033 GeO2 05 ROH 05 HF 7 H2O
The gel was prepared by hydrolyzing tetraethylorthosilicate (TEOS) in an
aqueous solution of 4-methyl-2367-tetrahydro-1H5H-pyrido[321-ij]
quinolinium hydroxide (ROH) then the appropriate amount of GeO2 was added
and the mixture was kept under stirring until the ethanol formed upon hydrolysis
of TEOS and the appropriate excess of water were evaporated to reach the gel
composition given above Finally an aqueous solution of HF (50) was added
and the mixture was introduced in a Teflon-lined stainless autoclave and heated
at 150ordmC for 5 days
After this time the autoclave was cooled down and the mixture was
filtered washed with water and dried at 100ordmC The final composition is given in
Table 1 The zeolite was calcined at 700ordmC in air
b) Al-containing ITQ-29 (sample SR386B) was synthesized in fluoride media in
the presence of Ge from a gel of the following composition
067 SiO2 033 GeO2 002 Al2O3 05 ROH 05 HF 7 H2O
11
The gel preparation was similar to that described for the Al-free ITQ-29
with the addition of Al isopropoxide as the source of Al and seeds of ITQ-29
(5 of the total inorganic oxides) in order to promote the crystallization
The crystallization was also carried out at 150ordmC for 5 days The final
composition is given in Table 1
c) The high Al content ITQ-29 zeolite (sample SR408A) was synthesized using
a mixture of OSDAacutes the quinolinium derivative and tetramethylammonium It
was obtained from a gel of the following composition
067 SiO2 033 GeO2 007 Al2O3 025 ROH 025 TMAOH 05 HF 7 H2O
The gel was prepared in a similar way than the previously described but adding
the required amount of tetraethylamonium hydroxide (TAMOH) together with the
quinolinium derivative hydroxide and seeds (5 of the total inorganic oxides) in
order to promote the crystallization The synthesis was carried out at 150ordmC for
3 days The final composition is given in Table 1
d) Purely siliceous ITQ-29 (sample SR455C) was prepared in fluoride media
from a gel of the following composition
100 SiO2 025 ROH 025 TMAOH 05 HF 2 H2O
The gel was prepared as described for SR346B but the addition of GeO2
was skipped and the crystallization was done at 135ordmC for 7 days The final
composition is given in table 1 The zeolite obtained was calcined at 700ordmC in
air
12
e) The Al-ITQ-29 zeolite employed for the catalytic experiments (Sample
SR454A) was synthesized from a gel of the following composition
091 SiO2 009 GeO2 002 Al2O3 025 ROH 025 TMAOH 05 HF 3 H2O
The crystallization was performed at 135ordmC for 2 days The final composition is
given in Table 1
The zeolite was previously calcined at 580ordmC for 3 hours in air flow
before the catalytic experiments
f) Pure silicoaluminate ITQ-29 zeolite (sample SR452B) was synthesized using
a mixture of OSDAacutes the quinolinium derivative and tetramethylammonium It
was obtained from a gel of the following composition
100 SiO2 001 Al2O3 025 ROH 025 TMAOH 05 HF 3 H2O
The gel was prepared in a similar way than the previously described but adding
the required amount of tetraethylamonium hydroxide (TMAOH) together with the
quinolinium derivative hydroxide and seeds of pure silica LTA (10 of the total
inorganic oxides) in order to promote the crystallization The synthesis was
carried out at 135ordmC for 5 days The final composition is given in Table 1
The XRD pattern shows that Al-ITQ-29 was obtained with a small impurity of
RUB-10 The Al-MAS-NMR spectrum shows a single resonance at approx 55
ppm indicating the tetrahedral coordination of Al in the sample Also this
sample when calcined was able to interact with ammonia and acetonitrile
showing the accessibility of the acid sites for small molecules
13
II Chemical analyses and 13 C-CP-MAS-NMR spectroscopy characterization
results
The chemical compositions of the ITQ-29 samples described above are given in
Table 1
Table 1 Chemical compositions of ITQ-29 samples expressed as molar composition per unit cellSample Si
(uc)Ge (uc)
Al (uc)
C (uc)
N(uc)
F(uc)
OSDA(uc)
TMA(uc)
SR346B 164 76 --- 278 21 20 21(a) 0
SR386B 155 82 03 284 23 16 23(a) 0
SR408A 145 78 17 305 31 10 20(b) 10
SR455C 240 --- --- 282 30 20 18(b) 12
SR454A 207 21 12 312 30 12 21(b) 09
SR452B 235 --- 05 294 33 18 18(b) 15
(a) Calculated from the N content
(b) Calculated from the N and C contents and assuming no decomposition of
the OSDA
14
Figure 3a 13C-CP-MAS-NMR spectra of the as-prepared ITQ-29 zeolites indicates the spinning side bands
The 13C-NMR spectra indicate that the OSDA remains nearly intact within
the pores of the ITQ-29 zeolites as deduced from the close resemblance of the
solid NMR spectra and the liquid phase spectrum of an aqueous solution of the
OSDA In the spectra of the samples prepared in presence of TMAOH a new
signal at 58 ppm (marked as ) appears indicating that TMA+ cations are
incorporated into the solids Finally some minor decomposition products are
also detected (marked as )
15
4 Structure Refinement of SiGe-LTA and pure silica LTA
Structure refinement of Ge containing ITQ-29 sample (SiGe = 2)
The calcined sample with SiGe molar ratio of 21 was measured in
vacuum and the corresponding X ray powder diffraction (XRD) pattern is shown
in Figure 4a This pattern was also indexed according to a cubic unit cell with
refined cell parameter equal to 120157(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
According to the refined scattering power at the T site and assuming that it is
filled the unit cell composition of the calcined sample is Si166 Ge74 O48 ie the
refined SiGe ratio is 22 The averaged distance (d) and angles ( ) from the
tetrahedron are d(T-O)=162Aring (O-T-O) =1094ordm (T-O-T) = 1531ordm The
refined atomic coordinates are listed in Table 2 and Figure 4a shows the very
good agreement between observed and calculated XRD patterns The details of
the Rietveld refinement are given in the Experimental Section
Table 2 Fractional atomic coordinates[ab] for ITQ-29 (SiGe=22)
Atom x y z No of positions
Wyckoff notation
T[c] 03700(1) 01840(1) 0 24 k
O1 12 02118(5) 0 12 h
O2 02946(5) 02946(5) 0 12 i
O3 03370(3) 01095(4) 01095(4) 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=120157(4)Aring)[b] Estimated standard deviations given in parentheses[c] Refined atomic occupations for site T 069(2)Si+031(2)Ge
16
Figure 4a Observed (crosses) and calculated (lines) XRD patterns of ITQ-29 as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections The arrows indicate the tow small regions excluded from the Rietveld refinement containing the diffraction lines of the platinum sample holder (Cu K12 radiation)
Structure refinement of pure silica ITQ-29 sample
The purely siliceous sample was measured after calcination at 700ordmC
under air and the corresponding X ray powder diffraction (XRD) pattern is
shown in Figure 4b This pattern was indexed according to a cubic unit cell with
refined cell parameter equal to 118671(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
The refined atomic coordinates are given in Table 3 and Figure 4b shows the
very good agreement between observed and calculated XRD patterns which
confirms that ITQ-29 has LTA structure type
17
Table 3 Fractional atomic coordinates[ab] for pure silica ITQ-29
Atom x y z No of positions
Wyckoff notation
Si 03683(3) 01847(3) 0 24 k
O1 12 02179(7) 0 12 h
O2 02939(7) x 0 12 i
O3 03429(4) 01098(7) y 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=118671(4)Aring)[b] Estimated standard deviations given in parentheses
Figure 4b Observed (crosses) and calculated (lines) XRD patterns of pure silica zeolite A as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections (Cu K12 radiation) To emphasize the high angle portion of the pattern the first reflection has been cut at half height
The refined unit cell volume is shorter by 64 Aring3 than the volume found for
the Ge containing form (ie 1671 Aring3 in front of 1735 Aring3) This result is consistent
with the larger ionic radius of Ge compared to Si that is also responsible of the
larger averaged T-O distance obtained in the Ge zeolite (d(T-O)=162Aring) than in
18
the pure silica ITQ-29 material (d(Si-O)=160Aring) The averaged distance (d) and
angles ( ) from the tetrahedron are d(Si-O)=160Aring (O-Si-O) = 1094ordm (Si-
O-Si) = 1533ordm It is notorious (see Table 4) that the most tensioned Si-O-Si
angle is the Si-O2-Si angle (1584ordm) which correspond to the oxygen that is
linking to neighboured D4R cages On the other hand the Si-O-Si angles
corresponding to oxygen atoms placed at that small D4R cage do not seem to
be strongly constrained giving Si-O1-Si and Si-O3-Si angles of 1517 and
1497ordm respectively
Table 4 Bond distances in Aring and bond angles in (ordm) with esds in parentheses
for pure Si zeolite A
Si - O1 1612(5)Si - O2 1568(7)Si - O3 1606(7) (2x)O1 - Si - O2 1102(4)O1 - Si - O3 1085(5) (2x)O2 - Si - O3 1106(6) (2x)O3 - Si - O3 1085(7)Si - O1 -Si 1517(6)Si- O2 - Si 1584(9)Si - O3 - Si 1497(9)
The details of the Rietveld refinement are given in the Experimental Section
Experimental section
XRD
The Ge containing ITQ-29 sample was calcined at 700ordmC for 1 hour The
pattern was measured at room temperature in vacuum on a Philips XPert
diffractometer with Bragg-Brentano geometry using a Pt sample holder and an
19
XCelerator detector Intensity data obtained with fixed divergence slit (025ordm)
Cu K radiation ( = 15406 15444Aring) Tube voltage and intensity 45 kV and
40 mA Step size and time 0017ordm 2 and 6000s
The pure silica ITQ-29 sample was calcined at 700ordmC in air for 3 hours
The pattern was measured at room temperature on a Philips XPert
diffractometer with Bragg-Brentano geometry using a conventional flat stage
holder and an XCelerator detector Intensity data obtained with fixed
divergence slit (0125ordm) Cu K radiation ( = 15406 15444Aring) Tube voltage
and intensity 45 kV and 40 mA Step size and time 0017ordm 2 and 6000s
Rietveld refinement
The Rietveld refinement of Ge-ITQ-29 data was performed with LSP7
using a 2 range from 135ordm to 642ordm with the regions between 39344 - 40177
and 45701 - 47220 excluded due to the appearance in these regions of the
(111) and (200) Pt diffraction peaks of the sample holder The transmission
coefficient at the Pt(111) Bragg position is 035 which was used for correcting
the finite film thickness of the sample Number of contributing reflections is 86
No geometric restraints used Number of structural parameters is 7 Number of
profile parameters is 8 including unit cell parameters and zero shift (-0020ordm 2)
with visually estimated background (Average background = 38000 counts)
Profile function used was Pearson VII Refined overall thermal vibration
coefficient B = 60Aring2 The residuals of the refinement were Rwp=0026
Rp=0018 2=50
The Rietveld refinement of the pure silica-ITQ-29 data with LSP7 was
performed using the measured 2 range from 5ordm to 75ordm Number of contributing
20
reflections is 186 No geometric restraints used Number of structural
parameters is 7 Number of profile parameters is 8 including unit cell
parameters and zero shift (-0055ordm 2) with visually estimated background
(Average background = 400 counts) Profile function used was Pearson VII
Refined overall thermal vibration coefficient B = 07Aring2 The residuals of the
refinement were Rwp=0097 Rp=0062 RB=0032 2=28
21
5 Comparison of commercial LTA samples with ITQ-29 zeolites
The XRD patterns of different commercial LTA zeolites are given for
comparison purposes
Zeolite 3A is the potassium form of the LTA zeolite having the following
composition
06 K2O 040 Na2O 1 Al2O3 20 plusmn 01SiO2 x H2O
4A is the same zeolite but in the sodium its formula is
1 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
Finally 5A is the Ca2+ exchanged material with the following composition
080 CaO 020 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
(all of them were purchased from Aldrich Co)
As can be seen all the commercial LTA samples posses a framework SiAl ratio
close to 1
22
In the figure It can be seen there that the peak intensities greatly depend on the
nature of the exchanged cation located within the cavities of the LTA structure
Also the X-ray diffraction lines of pure silica ITQ-29 zeolite are shifted towards
low 2θ values (ie higher d spacing) due to the smaller ionic radii of Si than that
of Al However the formation of pure silica LTA can be unambiguously
confirmed from the absence of non assigned diffraction lines and the goodness
of Rietveld refinement
23
- SUPPLEMENTARY MATERIAL
-
The gel preparation was similar to that described for the Al-free ITQ-29
with the addition of Al isopropoxide as the source of Al and seeds of ITQ-29
(5 of the total inorganic oxides) in order to promote the crystallization
The crystallization was also carried out at 150ordmC for 5 days The final
composition is given in Table 1
c) The high Al content ITQ-29 zeolite (sample SR408A) was synthesized using
a mixture of OSDAacutes the quinolinium derivative and tetramethylammonium It
was obtained from a gel of the following composition
067 SiO2 033 GeO2 007 Al2O3 025 ROH 025 TMAOH 05 HF 7 H2O
The gel was prepared in a similar way than the previously described but adding
the required amount of tetraethylamonium hydroxide (TAMOH) together with the
quinolinium derivative hydroxide and seeds (5 of the total inorganic oxides) in
order to promote the crystallization The synthesis was carried out at 150ordmC for
3 days The final composition is given in Table 1
d) Purely siliceous ITQ-29 (sample SR455C) was prepared in fluoride media
from a gel of the following composition
100 SiO2 025 ROH 025 TMAOH 05 HF 2 H2O
The gel was prepared as described for SR346B but the addition of GeO2
was skipped and the crystallization was done at 135ordmC for 7 days The final
composition is given in table 1 The zeolite obtained was calcined at 700ordmC in
air
12
e) The Al-ITQ-29 zeolite employed for the catalytic experiments (Sample
SR454A) was synthesized from a gel of the following composition
091 SiO2 009 GeO2 002 Al2O3 025 ROH 025 TMAOH 05 HF 3 H2O
The crystallization was performed at 135ordmC for 2 days The final composition is
given in Table 1
The zeolite was previously calcined at 580ordmC for 3 hours in air flow
before the catalytic experiments
f) Pure silicoaluminate ITQ-29 zeolite (sample SR452B) was synthesized using
a mixture of OSDAacutes the quinolinium derivative and tetramethylammonium It
was obtained from a gel of the following composition
100 SiO2 001 Al2O3 025 ROH 025 TMAOH 05 HF 3 H2O
The gel was prepared in a similar way than the previously described but adding
the required amount of tetraethylamonium hydroxide (TMAOH) together with the
quinolinium derivative hydroxide and seeds of pure silica LTA (10 of the total
inorganic oxides) in order to promote the crystallization The synthesis was
carried out at 135ordmC for 5 days The final composition is given in Table 1
The XRD pattern shows that Al-ITQ-29 was obtained with a small impurity of
RUB-10 The Al-MAS-NMR spectrum shows a single resonance at approx 55
ppm indicating the tetrahedral coordination of Al in the sample Also this
sample when calcined was able to interact with ammonia and acetonitrile
showing the accessibility of the acid sites for small molecules
13
II Chemical analyses and 13 C-CP-MAS-NMR spectroscopy characterization
results
The chemical compositions of the ITQ-29 samples described above are given in
Table 1
Table 1 Chemical compositions of ITQ-29 samples expressed as molar composition per unit cellSample Si
(uc)Ge (uc)
Al (uc)
C (uc)
N(uc)
F(uc)
OSDA(uc)
TMA(uc)
SR346B 164 76 --- 278 21 20 21(a) 0
SR386B 155 82 03 284 23 16 23(a) 0
SR408A 145 78 17 305 31 10 20(b) 10
SR455C 240 --- --- 282 30 20 18(b) 12
SR454A 207 21 12 312 30 12 21(b) 09
SR452B 235 --- 05 294 33 18 18(b) 15
(a) Calculated from the N content
(b) Calculated from the N and C contents and assuming no decomposition of
the OSDA
14
Figure 3a 13C-CP-MAS-NMR spectra of the as-prepared ITQ-29 zeolites indicates the spinning side bands
The 13C-NMR spectra indicate that the OSDA remains nearly intact within
the pores of the ITQ-29 zeolites as deduced from the close resemblance of the
solid NMR spectra and the liquid phase spectrum of an aqueous solution of the
OSDA In the spectra of the samples prepared in presence of TMAOH a new
signal at 58 ppm (marked as ) appears indicating that TMA+ cations are
incorporated into the solids Finally some minor decomposition products are
also detected (marked as )
15
4 Structure Refinement of SiGe-LTA and pure silica LTA
Structure refinement of Ge containing ITQ-29 sample (SiGe = 2)
The calcined sample with SiGe molar ratio of 21 was measured in
vacuum and the corresponding X ray powder diffraction (XRD) pattern is shown
in Figure 4a This pattern was also indexed according to a cubic unit cell with
refined cell parameter equal to 120157(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
According to the refined scattering power at the T site and assuming that it is
filled the unit cell composition of the calcined sample is Si166 Ge74 O48 ie the
refined SiGe ratio is 22 The averaged distance (d) and angles ( ) from the
tetrahedron are d(T-O)=162Aring (O-T-O) =1094ordm (T-O-T) = 1531ordm The
refined atomic coordinates are listed in Table 2 and Figure 4a shows the very
good agreement between observed and calculated XRD patterns The details of
the Rietveld refinement are given in the Experimental Section
Table 2 Fractional atomic coordinates[ab] for ITQ-29 (SiGe=22)
Atom x y z No of positions
Wyckoff notation
T[c] 03700(1) 01840(1) 0 24 k
O1 12 02118(5) 0 12 h
O2 02946(5) 02946(5) 0 12 i
O3 03370(3) 01095(4) 01095(4) 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=120157(4)Aring)[b] Estimated standard deviations given in parentheses[c] Refined atomic occupations for site T 069(2)Si+031(2)Ge
16
Figure 4a Observed (crosses) and calculated (lines) XRD patterns of ITQ-29 as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections The arrows indicate the tow small regions excluded from the Rietveld refinement containing the diffraction lines of the platinum sample holder (Cu K12 radiation)
Structure refinement of pure silica ITQ-29 sample
The purely siliceous sample was measured after calcination at 700ordmC
under air and the corresponding X ray powder diffraction (XRD) pattern is
shown in Figure 4b This pattern was indexed according to a cubic unit cell with
refined cell parameter equal to 118671(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
The refined atomic coordinates are given in Table 3 and Figure 4b shows the
very good agreement between observed and calculated XRD patterns which
confirms that ITQ-29 has LTA structure type
17
Table 3 Fractional atomic coordinates[ab] for pure silica ITQ-29
Atom x y z No of positions
Wyckoff notation
Si 03683(3) 01847(3) 0 24 k
O1 12 02179(7) 0 12 h
O2 02939(7) x 0 12 i
O3 03429(4) 01098(7) y 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=118671(4)Aring)[b] Estimated standard deviations given in parentheses
Figure 4b Observed (crosses) and calculated (lines) XRD patterns of pure silica zeolite A as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections (Cu K12 radiation) To emphasize the high angle portion of the pattern the first reflection has been cut at half height
The refined unit cell volume is shorter by 64 Aring3 than the volume found for
the Ge containing form (ie 1671 Aring3 in front of 1735 Aring3) This result is consistent
with the larger ionic radius of Ge compared to Si that is also responsible of the
larger averaged T-O distance obtained in the Ge zeolite (d(T-O)=162Aring) than in
18
the pure silica ITQ-29 material (d(Si-O)=160Aring) The averaged distance (d) and
angles ( ) from the tetrahedron are d(Si-O)=160Aring (O-Si-O) = 1094ordm (Si-
O-Si) = 1533ordm It is notorious (see Table 4) that the most tensioned Si-O-Si
angle is the Si-O2-Si angle (1584ordm) which correspond to the oxygen that is
linking to neighboured D4R cages On the other hand the Si-O-Si angles
corresponding to oxygen atoms placed at that small D4R cage do not seem to
be strongly constrained giving Si-O1-Si and Si-O3-Si angles of 1517 and
1497ordm respectively
Table 4 Bond distances in Aring and bond angles in (ordm) with esds in parentheses
for pure Si zeolite A
Si - O1 1612(5)Si - O2 1568(7)Si - O3 1606(7) (2x)O1 - Si - O2 1102(4)O1 - Si - O3 1085(5) (2x)O2 - Si - O3 1106(6) (2x)O3 - Si - O3 1085(7)Si - O1 -Si 1517(6)Si- O2 - Si 1584(9)Si - O3 - Si 1497(9)
The details of the Rietveld refinement are given in the Experimental Section
Experimental section
XRD
The Ge containing ITQ-29 sample was calcined at 700ordmC for 1 hour The
pattern was measured at room temperature in vacuum on a Philips XPert
diffractometer with Bragg-Brentano geometry using a Pt sample holder and an
19
XCelerator detector Intensity data obtained with fixed divergence slit (025ordm)
Cu K radiation ( = 15406 15444Aring) Tube voltage and intensity 45 kV and
40 mA Step size and time 0017ordm 2 and 6000s
The pure silica ITQ-29 sample was calcined at 700ordmC in air for 3 hours
The pattern was measured at room temperature on a Philips XPert
diffractometer with Bragg-Brentano geometry using a conventional flat stage
holder and an XCelerator detector Intensity data obtained with fixed
divergence slit (0125ordm) Cu K radiation ( = 15406 15444Aring) Tube voltage
and intensity 45 kV and 40 mA Step size and time 0017ordm 2 and 6000s
Rietveld refinement
The Rietveld refinement of Ge-ITQ-29 data was performed with LSP7
using a 2 range from 135ordm to 642ordm with the regions between 39344 - 40177
and 45701 - 47220 excluded due to the appearance in these regions of the
(111) and (200) Pt diffraction peaks of the sample holder The transmission
coefficient at the Pt(111) Bragg position is 035 which was used for correcting
the finite film thickness of the sample Number of contributing reflections is 86
No geometric restraints used Number of structural parameters is 7 Number of
profile parameters is 8 including unit cell parameters and zero shift (-0020ordm 2)
with visually estimated background (Average background = 38000 counts)
Profile function used was Pearson VII Refined overall thermal vibration
coefficient B = 60Aring2 The residuals of the refinement were Rwp=0026
Rp=0018 2=50
The Rietveld refinement of the pure silica-ITQ-29 data with LSP7 was
performed using the measured 2 range from 5ordm to 75ordm Number of contributing
20
reflections is 186 No geometric restraints used Number of structural
parameters is 7 Number of profile parameters is 8 including unit cell
parameters and zero shift (-0055ordm 2) with visually estimated background
(Average background = 400 counts) Profile function used was Pearson VII
Refined overall thermal vibration coefficient B = 07Aring2 The residuals of the
refinement were Rwp=0097 Rp=0062 RB=0032 2=28
21
5 Comparison of commercial LTA samples with ITQ-29 zeolites
The XRD patterns of different commercial LTA zeolites are given for
comparison purposes
Zeolite 3A is the potassium form of the LTA zeolite having the following
composition
06 K2O 040 Na2O 1 Al2O3 20 plusmn 01SiO2 x H2O
4A is the same zeolite but in the sodium its formula is
1 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
Finally 5A is the Ca2+ exchanged material with the following composition
080 CaO 020 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
(all of them were purchased from Aldrich Co)
As can be seen all the commercial LTA samples posses a framework SiAl ratio
close to 1
22
In the figure It can be seen there that the peak intensities greatly depend on the
nature of the exchanged cation located within the cavities of the LTA structure
Also the X-ray diffraction lines of pure silica ITQ-29 zeolite are shifted towards
low 2θ values (ie higher d spacing) due to the smaller ionic radii of Si than that
of Al However the formation of pure silica LTA can be unambiguously
confirmed from the absence of non assigned diffraction lines and the goodness
of Rietveld refinement
23
- SUPPLEMENTARY MATERIAL
-
e) The Al-ITQ-29 zeolite employed for the catalytic experiments (Sample
SR454A) was synthesized from a gel of the following composition
091 SiO2 009 GeO2 002 Al2O3 025 ROH 025 TMAOH 05 HF 3 H2O
The crystallization was performed at 135ordmC for 2 days The final composition is
given in Table 1
The zeolite was previously calcined at 580ordmC for 3 hours in air flow
before the catalytic experiments
f) Pure silicoaluminate ITQ-29 zeolite (sample SR452B) was synthesized using
a mixture of OSDAacutes the quinolinium derivative and tetramethylammonium It
was obtained from a gel of the following composition
100 SiO2 001 Al2O3 025 ROH 025 TMAOH 05 HF 3 H2O
The gel was prepared in a similar way than the previously described but adding
the required amount of tetraethylamonium hydroxide (TMAOH) together with the
quinolinium derivative hydroxide and seeds of pure silica LTA (10 of the total
inorganic oxides) in order to promote the crystallization The synthesis was
carried out at 135ordmC for 5 days The final composition is given in Table 1
The XRD pattern shows that Al-ITQ-29 was obtained with a small impurity of
RUB-10 The Al-MAS-NMR spectrum shows a single resonance at approx 55
ppm indicating the tetrahedral coordination of Al in the sample Also this
sample when calcined was able to interact with ammonia and acetonitrile
showing the accessibility of the acid sites for small molecules
13
II Chemical analyses and 13 C-CP-MAS-NMR spectroscopy characterization
results
The chemical compositions of the ITQ-29 samples described above are given in
Table 1
Table 1 Chemical compositions of ITQ-29 samples expressed as molar composition per unit cellSample Si
(uc)Ge (uc)
Al (uc)
C (uc)
N(uc)
F(uc)
OSDA(uc)
TMA(uc)
SR346B 164 76 --- 278 21 20 21(a) 0
SR386B 155 82 03 284 23 16 23(a) 0
SR408A 145 78 17 305 31 10 20(b) 10
SR455C 240 --- --- 282 30 20 18(b) 12
SR454A 207 21 12 312 30 12 21(b) 09
SR452B 235 --- 05 294 33 18 18(b) 15
(a) Calculated from the N content
(b) Calculated from the N and C contents and assuming no decomposition of
the OSDA
14
Figure 3a 13C-CP-MAS-NMR spectra of the as-prepared ITQ-29 zeolites indicates the spinning side bands
The 13C-NMR spectra indicate that the OSDA remains nearly intact within
the pores of the ITQ-29 zeolites as deduced from the close resemblance of the
solid NMR spectra and the liquid phase spectrum of an aqueous solution of the
OSDA In the spectra of the samples prepared in presence of TMAOH a new
signal at 58 ppm (marked as ) appears indicating that TMA+ cations are
incorporated into the solids Finally some minor decomposition products are
also detected (marked as )
15
4 Structure Refinement of SiGe-LTA and pure silica LTA
Structure refinement of Ge containing ITQ-29 sample (SiGe = 2)
The calcined sample with SiGe molar ratio of 21 was measured in
vacuum and the corresponding X ray powder diffraction (XRD) pattern is shown
in Figure 4a This pattern was also indexed according to a cubic unit cell with
refined cell parameter equal to 120157(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
According to the refined scattering power at the T site and assuming that it is
filled the unit cell composition of the calcined sample is Si166 Ge74 O48 ie the
refined SiGe ratio is 22 The averaged distance (d) and angles ( ) from the
tetrahedron are d(T-O)=162Aring (O-T-O) =1094ordm (T-O-T) = 1531ordm The
refined atomic coordinates are listed in Table 2 and Figure 4a shows the very
good agreement between observed and calculated XRD patterns The details of
the Rietveld refinement are given in the Experimental Section
Table 2 Fractional atomic coordinates[ab] for ITQ-29 (SiGe=22)
Atom x y z No of positions
Wyckoff notation
T[c] 03700(1) 01840(1) 0 24 k
O1 12 02118(5) 0 12 h
O2 02946(5) 02946(5) 0 12 i
O3 03370(3) 01095(4) 01095(4) 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=120157(4)Aring)[b] Estimated standard deviations given in parentheses[c] Refined atomic occupations for site T 069(2)Si+031(2)Ge
16
Figure 4a Observed (crosses) and calculated (lines) XRD patterns of ITQ-29 as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections The arrows indicate the tow small regions excluded from the Rietveld refinement containing the diffraction lines of the platinum sample holder (Cu K12 radiation)
Structure refinement of pure silica ITQ-29 sample
The purely siliceous sample was measured after calcination at 700ordmC
under air and the corresponding X ray powder diffraction (XRD) pattern is
shown in Figure 4b This pattern was indexed according to a cubic unit cell with
refined cell parameter equal to 118671(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
The refined atomic coordinates are given in Table 3 and Figure 4b shows the
very good agreement between observed and calculated XRD patterns which
confirms that ITQ-29 has LTA structure type
17
Table 3 Fractional atomic coordinates[ab] for pure silica ITQ-29
Atom x y z No of positions
Wyckoff notation
Si 03683(3) 01847(3) 0 24 k
O1 12 02179(7) 0 12 h
O2 02939(7) x 0 12 i
O3 03429(4) 01098(7) y 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=118671(4)Aring)[b] Estimated standard deviations given in parentheses
Figure 4b Observed (crosses) and calculated (lines) XRD patterns of pure silica zeolite A as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections (Cu K12 radiation) To emphasize the high angle portion of the pattern the first reflection has been cut at half height
The refined unit cell volume is shorter by 64 Aring3 than the volume found for
the Ge containing form (ie 1671 Aring3 in front of 1735 Aring3) This result is consistent
with the larger ionic radius of Ge compared to Si that is also responsible of the
larger averaged T-O distance obtained in the Ge zeolite (d(T-O)=162Aring) than in
18
the pure silica ITQ-29 material (d(Si-O)=160Aring) The averaged distance (d) and
angles ( ) from the tetrahedron are d(Si-O)=160Aring (O-Si-O) = 1094ordm (Si-
O-Si) = 1533ordm It is notorious (see Table 4) that the most tensioned Si-O-Si
angle is the Si-O2-Si angle (1584ordm) which correspond to the oxygen that is
linking to neighboured D4R cages On the other hand the Si-O-Si angles
corresponding to oxygen atoms placed at that small D4R cage do not seem to
be strongly constrained giving Si-O1-Si and Si-O3-Si angles of 1517 and
1497ordm respectively
Table 4 Bond distances in Aring and bond angles in (ordm) with esds in parentheses
for pure Si zeolite A
Si - O1 1612(5)Si - O2 1568(7)Si - O3 1606(7) (2x)O1 - Si - O2 1102(4)O1 - Si - O3 1085(5) (2x)O2 - Si - O3 1106(6) (2x)O3 - Si - O3 1085(7)Si - O1 -Si 1517(6)Si- O2 - Si 1584(9)Si - O3 - Si 1497(9)
The details of the Rietveld refinement are given in the Experimental Section
Experimental section
XRD
The Ge containing ITQ-29 sample was calcined at 700ordmC for 1 hour The
pattern was measured at room temperature in vacuum on a Philips XPert
diffractometer with Bragg-Brentano geometry using a Pt sample holder and an
19
XCelerator detector Intensity data obtained with fixed divergence slit (025ordm)
Cu K radiation ( = 15406 15444Aring) Tube voltage and intensity 45 kV and
40 mA Step size and time 0017ordm 2 and 6000s
The pure silica ITQ-29 sample was calcined at 700ordmC in air for 3 hours
The pattern was measured at room temperature on a Philips XPert
diffractometer with Bragg-Brentano geometry using a conventional flat stage
holder and an XCelerator detector Intensity data obtained with fixed
divergence slit (0125ordm) Cu K radiation ( = 15406 15444Aring) Tube voltage
and intensity 45 kV and 40 mA Step size and time 0017ordm 2 and 6000s
Rietveld refinement
The Rietveld refinement of Ge-ITQ-29 data was performed with LSP7
using a 2 range from 135ordm to 642ordm with the regions between 39344 - 40177
and 45701 - 47220 excluded due to the appearance in these regions of the
(111) and (200) Pt diffraction peaks of the sample holder The transmission
coefficient at the Pt(111) Bragg position is 035 which was used for correcting
the finite film thickness of the sample Number of contributing reflections is 86
No geometric restraints used Number of structural parameters is 7 Number of
profile parameters is 8 including unit cell parameters and zero shift (-0020ordm 2)
with visually estimated background (Average background = 38000 counts)
Profile function used was Pearson VII Refined overall thermal vibration
coefficient B = 60Aring2 The residuals of the refinement were Rwp=0026
Rp=0018 2=50
The Rietveld refinement of the pure silica-ITQ-29 data with LSP7 was
performed using the measured 2 range from 5ordm to 75ordm Number of contributing
20
reflections is 186 No geometric restraints used Number of structural
parameters is 7 Number of profile parameters is 8 including unit cell
parameters and zero shift (-0055ordm 2) with visually estimated background
(Average background = 400 counts) Profile function used was Pearson VII
Refined overall thermal vibration coefficient B = 07Aring2 The residuals of the
refinement were Rwp=0097 Rp=0062 RB=0032 2=28
21
5 Comparison of commercial LTA samples with ITQ-29 zeolites
The XRD patterns of different commercial LTA zeolites are given for
comparison purposes
Zeolite 3A is the potassium form of the LTA zeolite having the following
composition
06 K2O 040 Na2O 1 Al2O3 20 plusmn 01SiO2 x H2O
4A is the same zeolite but in the sodium its formula is
1 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
Finally 5A is the Ca2+ exchanged material with the following composition
080 CaO 020 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
(all of them were purchased from Aldrich Co)
As can be seen all the commercial LTA samples posses a framework SiAl ratio
close to 1
22
In the figure It can be seen there that the peak intensities greatly depend on the
nature of the exchanged cation located within the cavities of the LTA structure
Also the X-ray diffraction lines of pure silica ITQ-29 zeolite are shifted towards
low 2θ values (ie higher d spacing) due to the smaller ionic radii of Si than that
of Al However the formation of pure silica LTA can be unambiguously
confirmed from the absence of non assigned diffraction lines and the goodness
of Rietveld refinement
23
- SUPPLEMENTARY MATERIAL
-
II Chemical analyses and 13 C-CP-MAS-NMR spectroscopy characterization
results
The chemical compositions of the ITQ-29 samples described above are given in
Table 1
Table 1 Chemical compositions of ITQ-29 samples expressed as molar composition per unit cellSample Si
(uc)Ge (uc)
Al (uc)
C (uc)
N(uc)
F(uc)
OSDA(uc)
TMA(uc)
SR346B 164 76 --- 278 21 20 21(a) 0
SR386B 155 82 03 284 23 16 23(a) 0
SR408A 145 78 17 305 31 10 20(b) 10
SR455C 240 --- --- 282 30 20 18(b) 12
SR454A 207 21 12 312 30 12 21(b) 09
SR452B 235 --- 05 294 33 18 18(b) 15
(a) Calculated from the N content
(b) Calculated from the N and C contents and assuming no decomposition of
the OSDA
14
Figure 3a 13C-CP-MAS-NMR spectra of the as-prepared ITQ-29 zeolites indicates the spinning side bands
The 13C-NMR spectra indicate that the OSDA remains nearly intact within
the pores of the ITQ-29 zeolites as deduced from the close resemblance of the
solid NMR spectra and the liquid phase spectrum of an aqueous solution of the
OSDA In the spectra of the samples prepared in presence of TMAOH a new
signal at 58 ppm (marked as ) appears indicating that TMA+ cations are
incorporated into the solids Finally some minor decomposition products are
also detected (marked as )
15
4 Structure Refinement of SiGe-LTA and pure silica LTA
Structure refinement of Ge containing ITQ-29 sample (SiGe = 2)
The calcined sample with SiGe molar ratio of 21 was measured in
vacuum and the corresponding X ray powder diffraction (XRD) pattern is shown
in Figure 4a This pattern was also indexed according to a cubic unit cell with
refined cell parameter equal to 120157(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
According to the refined scattering power at the T site and assuming that it is
filled the unit cell composition of the calcined sample is Si166 Ge74 O48 ie the
refined SiGe ratio is 22 The averaged distance (d) and angles ( ) from the
tetrahedron are d(T-O)=162Aring (O-T-O) =1094ordm (T-O-T) = 1531ordm The
refined atomic coordinates are listed in Table 2 and Figure 4a shows the very
good agreement between observed and calculated XRD patterns The details of
the Rietveld refinement are given in the Experimental Section
Table 2 Fractional atomic coordinates[ab] for ITQ-29 (SiGe=22)
Atom x y z No of positions
Wyckoff notation
T[c] 03700(1) 01840(1) 0 24 k
O1 12 02118(5) 0 12 h
O2 02946(5) 02946(5) 0 12 i
O3 03370(3) 01095(4) 01095(4) 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=120157(4)Aring)[b] Estimated standard deviations given in parentheses[c] Refined atomic occupations for site T 069(2)Si+031(2)Ge
16
Figure 4a Observed (crosses) and calculated (lines) XRD patterns of ITQ-29 as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections The arrows indicate the tow small regions excluded from the Rietveld refinement containing the diffraction lines of the platinum sample holder (Cu K12 radiation)
Structure refinement of pure silica ITQ-29 sample
The purely siliceous sample was measured after calcination at 700ordmC
under air and the corresponding X ray powder diffraction (XRD) pattern is
shown in Figure 4b This pattern was indexed according to a cubic unit cell with
refined cell parameter equal to 118671(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
The refined atomic coordinates are given in Table 3 and Figure 4b shows the
very good agreement between observed and calculated XRD patterns which
confirms that ITQ-29 has LTA structure type
17
Table 3 Fractional atomic coordinates[ab] for pure silica ITQ-29
Atom x y z No of positions
Wyckoff notation
Si 03683(3) 01847(3) 0 24 k
O1 12 02179(7) 0 12 h
O2 02939(7) x 0 12 i
O3 03429(4) 01098(7) y 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=118671(4)Aring)[b] Estimated standard deviations given in parentheses
Figure 4b Observed (crosses) and calculated (lines) XRD patterns of pure silica zeolite A as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections (Cu K12 radiation) To emphasize the high angle portion of the pattern the first reflection has been cut at half height
The refined unit cell volume is shorter by 64 Aring3 than the volume found for
the Ge containing form (ie 1671 Aring3 in front of 1735 Aring3) This result is consistent
with the larger ionic radius of Ge compared to Si that is also responsible of the
larger averaged T-O distance obtained in the Ge zeolite (d(T-O)=162Aring) than in
18
the pure silica ITQ-29 material (d(Si-O)=160Aring) The averaged distance (d) and
angles ( ) from the tetrahedron are d(Si-O)=160Aring (O-Si-O) = 1094ordm (Si-
O-Si) = 1533ordm It is notorious (see Table 4) that the most tensioned Si-O-Si
angle is the Si-O2-Si angle (1584ordm) which correspond to the oxygen that is
linking to neighboured D4R cages On the other hand the Si-O-Si angles
corresponding to oxygen atoms placed at that small D4R cage do not seem to
be strongly constrained giving Si-O1-Si and Si-O3-Si angles of 1517 and
1497ordm respectively
Table 4 Bond distances in Aring and bond angles in (ordm) with esds in parentheses
for pure Si zeolite A
Si - O1 1612(5)Si - O2 1568(7)Si - O3 1606(7) (2x)O1 - Si - O2 1102(4)O1 - Si - O3 1085(5) (2x)O2 - Si - O3 1106(6) (2x)O3 - Si - O3 1085(7)Si - O1 -Si 1517(6)Si- O2 - Si 1584(9)Si - O3 - Si 1497(9)
The details of the Rietveld refinement are given in the Experimental Section
Experimental section
XRD
The Ge containing ITQ-29 sample was calcined at 700ordmC for 1 hour The
pattern was measured at room temperature in vacuum on a Philips XPert
diffractometer with Bragg-Brentano geometry using a Pt sample holder and an
19
XCelerator detector Intensity data obtained with fixed divergence slit (025ordm)
Cu K radiation ( = 15406 15444Aring) Tube voltage and intensity 45 kV and
40 mA Step size and time 0017ordm 2 and 6000s
The pure silica ITQ-29 sample was calcined at 700ordmC in air for 3 hours
The pattern was measured at room temperature on a Philips XPert
diffractometer with Bragg-Brentano geometry using a conventional flat stage
holder and an XCelerator detector Intensity data obtained with fixed
divergence slit (0125ordm) Cu K radiation ( = 15406 15444Aring) Tube voltage
and intensity 45 kV and 40 mA Step size and time 0017ordm 2 and 6000s
Rietveld refinement
The Rietveld refinement of Ge-ITQ-29 data was performed with LSP7
using a 2 range from 135ordm to 642ordm with the regions between 39344 - 40177
and 45701 - 47220 excluded due to the appearance in these regions of the
(111) and (200) Pt diffraction peaks of the sample holder The transmission
coefficient at the Pt(111) Bragg position is 035 which was used for correcting
the finite film thickness of the sample Number of contributing reflections is 86
No geometric restraints used Number of structural parameters is 7 Number of
profile parameters is 8 including unit cell parameters and zero shift (-0020ordm 2)
with visually estimated background (Average background = 38000 counts)
Profile function used was Pearson VII Refined overall thermal vibration
coefficient B = 60Aring2 The residuals of the refinement were Rwp=0026
Rp=0018 2=50
The Rietveld refinement of the pure silica-ITQ-29 data with LSP7 was
performed using the measured 2 range from 5ordm to 75ordm Number of contributing
20
reflections is 186 No geometric restraints used Number of structural
parameters is 7 Number of profile parameters is 8 including unit cell
parameters and zero shift (-0055ordm 2) with visually estimated background
(Average background = 400 counts) Profile function used was Pearson VII
Refined overall thermal vibration coefficient B = 07Aring2 The residuals of the
refinement were Rwp=0097 Rp=0062 RB=0032 2=28
21
5 Comparison of commercial LTA samples with ITQ-29 zeolites
The XRD patterns of different commercial LTA zeolites are given for
comparison purposes
Zeolite 3A is the potassium form of the LTA zeolite having the following
composition
06 K2O 040 Na2O 1 Al2O3 20 plusmn 01SiO2 x H2O
4A is the same zeolite but in the sodium its formula is
1 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
Finally 5A is the Ca2+ exchanged material with the following composition
080 CaO 020 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
(all of them were purchased from Aldrich Co)
As can be seen all the commercial LTA samples posses a framework SiAl ratio
close to 1
22
In the figure It can be seen there that the peak intensities greatly depend on the
nature of the exchanged cation located within the cavities of the LTA structure
Also the X-ray diffraction lines of pure silica ITQ-29 zeolite are shifted towards
low 2θ values (ie higher d spacing) due to the smaller ionic radii of Si than that
of Al However the formation of pure silica LTA can be unambiguously
confirmed from the absence of non assigned diffraction lines and the goodness
of Rietveld refinement
23
- SUPPLEMENTARY MATERIAL
-
The 13C-NMR spectra indicate that the OSDA remains nearly intact within
the pores of the ITQ-29 zeolites as deduced from the close resemblance of the
solid NMR spectra and the liquid phase spectrum of an aqueous solution of the
OSDA In the spectra of the samples prepared in presence of TMAOH a new
signal at 58 ppm (marked as ) appears indicating that TMA+ cations are
incorporated into the solids Finally some minor decomposition products are
also detected (marked as )
15
4 Structure Refinement of SiGe-LTA and pure silica LTA
Structure refinement of Ge containing ITQ-29 sample (SiGe = 2)
The calcined sample with SiGe molar ratio of 21 was measured in
vacuum and the corresponding X ray powder diffraction (XRD) pattern is shown
in Figure 4a This pattern was also indexed according to a cubic unit cell with
refined cell parameter equal to 120157(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
According to the refined scattering power at the T site and assuming that it is
filled the unit cell composition of the calcined sample is Si166 Ge74 O48 ie the
refined SiGe ratio is 22 The averaged distance (d) and angles ( ) from the
tetrahedron are d(T-O)=162Aring (O-T-O) =1094ordm (T-O-T) = 1531ordm The
refined atomic coordinates are listed in Table 2 and Figure 4a shows the very
good agreement between observed and calculated XRD patterns The details of
the Rietveld refinement are given in the Experimental Section
Table 2 Fractional atomic coordinates[ab] for ITQ-29 (SiGe=22)
Atom x y z No of positions
Wyckoff notation
T[c] 03700(1) 01840(1) 0 24 k
O1 12 02118(5) 0 12 h
O2 02946(5) 02946(5) 0 12 i
O3 03370(3) 01095(4) 01095(4) 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=120157(4)Aring)[b] Estimated standard deviations given in parentheses[c] Refined atomic occupations for site T 069(2)Si+031(2)Ge
16
Figure 4a Observed (crosses) and calculated (lines) XRD patterns of ITQ-29 as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections The arrows indicate the tow small regions excluded from the Rietveld refinement containing the diffraction lines of the platinum sample holder (Cu K12 radiation)
Structure refinement of pure silica ITQ-29 sample
The purely siliceous sample was measured after calcination at 700ordmC
under air and the corresponding X ray powder diffraction (XRD) pattern is
shown in Figure 4b This pattern was indexed according to a cubic unit cell with
refined cell parameter equal to 118671(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
The refined atomic coordinates are given in Table 3 and Figure 4b shows the
very good agreement between observed and calculated XRD patterns which
confirms that ITQ-29 has LTA structure type
17
Table 3 Fractional atomic coordinates[ab] for pure silica ITQ-29
Atom x y z No of positions
Wyckoff notation
Si 03683(3) 01847(3) 0 24 k
O1 12 02179(7) 0 12 h
O2 02939(7) x 0 12 i
O3 03429(4) 01098(7) y 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=118671(4)Aring)[b] Estimated standard deviations given in parentheses
Figure 4b Observed (crosses) and calculated (lines) XRD patterns of pure silica zeolite A as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections (Cu K12 radiation) To emphasize the high angle portion of the pattern the first reflection has been cut at half height
The refined unit cell volume is shorter by 64 Aring3 than the volume found for
the Ge containing form (ie 1671 Aring3 in front of 1735 Aring3) This result is consistent
with the larger ionic radius of Ge compared to Si that is also responsible of the
larger averaged T-O distance obtained in the Ge zeolite (d(T-O)=162Aring) than in
18
the pure silica ITQ-29 material (d(Si-O)=160Aring) The averaged distance (d) and
angles ( ) from the tetrahedron are d(Si-O)=160Aring (O-Si-O) = 1094ordm (Si-
O-Si) = 1533ordm It is notorious (see Table 4) that the most tensioned Si-O-Si
angle is the Si-O2-Si angle (1584ordm) which correspond to the oxygen that is
linking to neighboured D4R cages On the other hand the Si-O-Si angles
corresponding to oxygen atoms placed at that small D4R cage do not seem to
be strongly constrained giving Si-O1-Si and Si-O3-Si angles of 1517 and
1497ordm respectively
Table 4 Bond distances in Aring and bond angles in (ordm) with esds in parentheses
for pure Si zeolite A
Si - O1 1612(5)Si - O2 1568(7)Si - O3 1606(7) (2x)O1 - Si - O2 1102(4)O1 - Si - O3 1085(5) (2x)O2 - Si - O3 1106(6) (2x)O3 - Si - O3 1085(7)Si - O1 -Si 1517(6)Si- O2 - Si 1584(9)Si - O3 - Si 1497(9)
The details of the Rietveld refinement are given in the Experimental Section
Experimental section
XRD
The Ge containing ITQ-29 sample was calcined at 700ordmC for 1 hour The
pattern was measured at room temperature in vacuum on a Philips XPert
diffractometer with Bragg-Brentano geometry using a Pt sample holder and an
19
XCelerator detector Intensity data obtained with fixed divergence slit (025ordm)
Cu K radiation ( = 15406 15444Aring) Tube voltage and intensity 45 kV and
40 mA Step size and time 0017ordm 2 and 6000s
The pure silica ITQ-29 sample was calcined at 700ordmC in air for 3 hours
The pattern was measured at room temperature on a Philips XPert
diffractometer with Bragg-Brentano geometry using a conventional flat stage
holder and an XCelerator detector Intensity data obtained with fixed
divergence slit (0125ordm) Cu K radiation ( = 15406 15444Aring) Tube voltage
and intensity 45 kV and 40 mA Step size and time 0017ordm 2 and 6000s
Rietveld refinement
The Rietveld refinement of Ge-ITQ-29 data was performed with LSP7
using a 2 range from 135ordm to 642ordm with the regions between 39344 - 40177
and 45701 - 47220 excluded due to the appearance in these regions of the
(111) and (200) Pt diffraction peaks of the sample holder The transmission
coefficient at the Pt(111) Bragg position is 035 which was used for correcting
the finite film thickness of the sample Number of contributing reflections is 86
No geometric restraints used Number of structural parameters is 7 Number of
profile parameters is 8 including unit cell parameters and zero shift (-0020ordm 2)
with visually estimated background (Average background = 38000 counts)
Profile function used was Pearson VII Refined overall thermal vibration
coefficient B = 60Aring2 The residuals of the refinement were Rwp=0026
Rp=0018 2=50
The Rietveld refinement of the pure silica-ITQ-29 data with LSP7 was
performed using the measured 2 range from 5ordm to 75ordm Number of contributing
20
reflections is 186 No geometric restraints used Number of structural
parameters is 7 Number of profile parameters is 8 including unit cell
parameters and zero shift (-0055ordm 2) with visually estimated background
(Average background = 400 counts) Profile function used was Pearson VII
Refined overall thermal vibration coefficient B = 07Aring2 The residuals of the
refinement were Rwp=0097 Rp=0062 RB=0032 2=28
21
5 Comparison of commercial LTA samples with ITQ-29 zeolites
The XRD patterns of different commercial LTA zeolites are given for
comparison purposes
Zeolite 3A is the potassium form of the LTA zeolite having the following
composition
06 K2O 040 Na2O 1 Al2O3 20 plusmn 01SiO2 x H2O
4A is the same zeolite but in the sodium its formula is
1 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
Finally 5A is the Ca2+ exchanged material with the following composition
080 CaO 020 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
(all of them were purchased from Aldrich Co)
As can be seen all the commercial LTA samples posses a framework SiAl ratio
close to 1
22
In the figure It can be seen there that the peak intensities greatly depend on the
nature of the exchanged cation located within the cavities of the LTA structure
Also the X-ray diffraction lines of pure silica ITQ-29 zeolite are shifted towards
low 2θ values (ie higher d spacing) due to the smaller ionic radii of Si than that
of Al However the formation of pure silica LTA can be unambiguously
confirmed from the absence of non assigned diffraction lines and the goodness
of Rietveld refinement
23
- SUPPLEMENTARY MATERIAL
-
4 Structure Refinement of SiGe-LTA and pure silica LTA
Structure refinement of Ge containing ITQ-29 sample (SiGe = 2)
The calcined sample with SiGe molar ratio of 21 was measured in
vacuum and the corresponding X ray powder diffraction (XRD) pattern is shown
in Figure 4a This pattern was also indexed according to a cubic unit cell with
refined cell parameter equal to 120157(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
According to the refined scattering power at the T site and assuming that it is
filled the unit cell composition of the calcined sample is Si166 Ge74 O48 ie the
refined SiGe ratio is 22 The averaged distance (d) and angles ( ) from the
tetrahedron are d(T-O)=162Aring (O-T-O) =1094ordm (T-O-T) = 1531ordm The
refined atomic coordinates are listed in Table 2 and Figure 4a shows the very
good agreement between observed and calculated XRD patterns The details of
the Rietveld refinement are given in the Experimental Section
Table 2 Fractional atomic coordinates[ab] for ITQ-29 (SiGe=22)
Atom x y z No of positions
Wyckoff notation
T[c] 03700(1) 01840(1) 0 24 k
O1 12 02118(5) 0 12 h
O2 02946(5) 02946(5) 0 12 i
O3 03370(3) 01095(4) 01095(4) 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=120157(4)Aring)[b] Estimated standard deviations given in parentheses[c] Refined atomic occupations for site T 069(2)Si+031(2)Ge
16
Figure 4a Observed (crosses) and calculated (lines) XRD patterns of ITQ-29 as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections The arrows indicate the tow small regions excluded from the Rietveld refinement containing the diffraction lines of the platinum sample holder (Cu K12 radiation)
Structure refinement of pure silica ITQ-29 sample
The purely siliceous sample was measured after calcination at 700ordmC
under air and the corresponding X ray powder diffraction (XRD) pattern is
shown in Figure 4b This pattern was indexed according to a cubic unit cell with
refined cell parameter equal to 118671(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
The refined atomic coordinates are given in Table 3 and Figure 4b shows the
very good agreement between observed and calculated XRD patterns which
confirms that ITQ-29 has LTA structure type
17
Table 3 Fractional atomic coordinates[ab] for pure silica ITQ-29
Atom x y z No of positions
Wyckoff notation
Si 03683(3) 01847(3) 0 24 k
O1 12 02179(7) 0 12 h
O2 02939(7) x 0 12 i
O3 03429(4) 01098(7) y 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=118671(4)Aring)[b] Estimated standard deviations given in parentheses
Figure 4b Observed (crosses) and calculated (lines) XRD patterns of pure silica zeolite A as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections (Cu K12 radiation) To emphasize the high angle portion of the pattern the first reflection has been cut at half height
The refined unit cell volume is shorter by 64 Aring3 than the volume found for
the Ge containing form (ie 1671 Aring3 in front of 1735 Aring3) This result is consistent
with the larger ionic radius of Ge compared to Si that is also responsible of the
larger averaged T-O distance obtained in the Ge zeolite (d(T-O)=162Aring) than in
18
the pure silica ITQ-29 material (d(Si-O)=160Aring) The averaged distance (d) and
angles ( ) from the tetrahedron are d(Si-O)=160Aring (O-Si-O) = 1094ordm (Si-
O-Si) = 1533ordm It is notorious (see Table 4) that the most tensioned Si-O-Si
angle is the Si-O2-Si angle (1584ordm) which correspond to the oxygen that is
linking to neighboured D4R cages On the other hand the Si-O-Si angles
corresponding to oxygen atoms placed at that small D4R cage do not seem to
be strongly constrained giving Si-O1-Si and Si-O3-Si angles of 1517 and
1497ordm respectively
Table 4 Bond distances in Aring and bond angles in (ordm) with esds in parentheses
for pure Si zeolite A
Si - O1 1612(5)Si - O2 1568(7)Si - O3 1606(7) (2x)O1 - Si - O2 1102(4)O1 - Si - O3 1085(5) (2x)O2 - Si - O3 1106(6) (2x)O3 - Si - O3 1085(7)Si - O1 -Si 1517(6)Si- O2 - Si 1584(9)Si - O3 - Si 1497(9)
The details of the Rietveld refinement are given in the Experimental Section
Experimental section
XRD
The Ge containing ITQ-29 sample was calcined at 700ordmC for 1 hour The
pattern was measured at room temperature in vacuum on a Philips XPert
diffractometer with Bragg-Brentano geometry using a Pt sample holder and an
19
XCelerator detector Intensity data obtained with fixed divergence slit (025ordm)
Cu K radiation ( = 15406 15444Aring) Tube voltage and intensity 45 kV and
40 mA Step size and time 0017ordm 2 and 6000s
The pure silica ITQ-29 sample was calcined at 700ordmC in air for 3 hours
The pattern was measured at room temperature on a Philips XPert
diffractometer with Bragg-Brentano geometry using a conventional flat stage
holder and an XCelerator detector Intensity data obtained with fixed
divergence slit (0125ordm) Cu K radiation ( = 15406 15444Aring) Tube voltage
and intensity 45 kV and 40 mA Step size and time 0017ordm 2 and 6000s
Rietveld refinement
The Rietveld refinement of Ge-ITQ-29 data was performed with LSP7
using a 2 range from 135ordm to 642ordm with the regions between 39344 - 40177
and 45701 - 47220 excluded due to the appearance in these regions of the
(111) and (200) Pt diffraction peaks of the sample holder The transmission
coefficient at the Pt(111) Bragg position is 035 which was used for correcting
the finite film thickness of the sample Number of contributing reflections is 86
No geometric restraints used Number of structural parameters is 7 Number of
profile parameters is 8 including unit cell parameters and zero shift (-0020ordm 2)
with visually estimated background (Average background = 38000 counts)
Profile function used was Pearson VII Refined overall thermal vibration
coefficient B = 60Aring2 The residuals of the refinement were Rwp=0026
Rp=0018 2=50
The Rietveld refinement of the pure silica-ITQ-29 data with LSP7 was
performed using the measured 2 range from 5ordm to 75ordm Number of contributing
20
reflections is 186 No geometric restraints used Number of structural
parameters is 7 Number of profile parameters is 8 including unit cell
parameters and zero shift (-0055ordm 2) with visually estimated background
(Average background = 400 counts) Profile function used was Pearson VII
Refined overall thermal vibration coefficient B = 07Aring2 The residuals of the
refinement were Rwp=0097 Rp=0062 RB=0032 2=28
21
5 Comparison of commercial LTA samples with ITQ-29 zeolites
The XRD patterns of different commercial LTA zeolites are given for
comparison purposes
Zeolite 3A is the potassium form of the LTA zeolite having the following
composition
06 K2O 040 Na2O 1 Al2O3 20 plusmn 01SiO2 x H2O
4A is the same zeolite but in the sodium its formula is
1 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
Finally 5A is the Ca2+ exchanged material with the following composition
080 CaO 020 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
(all of them were purchased from Aldrich Co)
As can be seen all the commercial LTA samples posses a framework SiAl ratio
close to 1
22
In the figure It can be seen there that the peak intensities greatly depend on the
nature of the exchanged cation located within the cavities of the LTA structure
Also the X-ray diffraction lines of pure silica ITQ-29 zeolite are shifted towards
low 2θ values (ie higher d spacing) due to the smaller ionic radii of Si than that
of Al However the formation of pure silica LTA can be unambiguously
confirmed from the absence of non assigned diffraction lines and the goodness
of Rietveld refinement
23
- SUPPLEMENTARY MATERIAL
-
Figure 4a Observed (crosses) and calculated (lines) XRD patterns of ITQ-29 as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections The arrows indicate the tow small regions excluded from the Rietveld refinement containing the diffraction lines of the platinum sample holder (Cu K12 radiation)
Structure refinement of pure silica ITQ-29 sample
The purely siliceous sample was measured after calcination at 700ordmC
under air and the corresponding X ray powder diffraction (XRD) pattern is
shown in Figure 4b This pattern was indexed according to a cubic unit cell with
refined cell parameter equal to 118671(4) Aring For the Rietveld refinement the
LTA zeolite structure type with Pm3m space group symmetry was employed
The refined atomic coordinates are given in Table 3 and Figure 4b shows the
very good agreement between observed and calculated XRD patterns which
confirms that ITQ-29 has LTA structure type
17
Table 3 Fractional atomic coordinates[ab] for pure silica ITQ-29
Atom x y z No of positions
Wyckoff notation
Si 03683(3) 01847(3) 0 24 k
O1 12 02179(7) 0 12 h
O2 02939(7) x 0 12 i
O3 03429(4) 01098(7) y 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=118671(4)Aring)[b] Estimated standard deviations given in parentheses
Figure 4b Observed (crosses) and calculated (lines) XRD patterns of pure silica zeolite A as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections (Cu K12 radiation) To emphasize the high angle portion of the pattern the first reflection has been cut at half height
The refined unit cell volume is shorter by 64 Aring3 than the volume found for
the Ge containing form (ie 1671 Aring3 in front of 1735 Aring3) This result is consistent
with the larger ionic radius of Ge compared to Si that is also responsible of the
larger averaged T-O distance obtained in the Ge zeolite (d(T-O)=162Aring) than in
18
the pure silica ITQ-29 material (d(Si-O)=160Aring) The averaged distance (d) and
angles ( ) from the tetrahedron are d(Si-O)=160Aring (O-Si-O) = 1094ordm (Si-
O-Si) = 1533ordm It is notorious (see Table 4) that the most tensioned Si-O-Si
angle is the Si-O2-Si angle (1584ordm) which correspond to the oxygen that is
linking to neighboured D4R cages On the other hand the Si-O-Si angles
corresponding to oxygen atoms placed at that small D4R cage do not seem to
be strongly constrained giving Si-O1-Si and Si-O3-Si angles of 1517 and
1497ordm respectively
Table 4 Bond distances in Aring and bond angles in (ordm) with esds in parentheses
for pure Si zeolite A
Si - O1 1612(5)Si - O2 1568(7)Si - O3 1606(7) (2x)O1 - Si - O2 1102(4)O1 - Si - O3 1085(5) (2x)O2 - Si - O3 1106(6) (2x)O3 - Si - O3 1085(7)Si - O1 -Si 1517(6)Si- O2 - Si 1584(9)Si - O3 - Si 1497(9)
The details of the Rietveld refinement are given in the Experimental Section
Experimental section
XRD
The Ge containing ITQ-29 sample was calcined at 700ordmC for 1 hour The
pattern was measured at room temperature in vacuum on a Philips XPert
diffractometer with Bragg-Brentano geometry using a Pt sample holder and an
19
XCelerator detector Intensity data obtained with fixed divergence slit (025ordm)
Cu K radiation ( = 15406 15444Aring) Tube voltage and intensity 45 kV and
40 mA Step size and time 0017ordm 2 and 6000s
The pure silica ITQ-29 sample was calcined at 700ordmC in air for 3 hours
The pattern was measured at room temperature on a Philips XPert
diffractometer with Bragg-Brentano geometry using a conventional flat stage
holder and an XCelerator detector Intensity data obtained with fixed
divergence slit (0125ordm) Cu K radiation ( = 15406 15444Aring) Tube voltage
and intensity 45 kV and 40 mA Step size and time 0017ordm 2 and 6000s
Rietveld refinement
The Rietveld refinement of Ge-ITQ-29 data was performed with LSP7
using a 2 range from 135ordm to 642ordm with the regions between 39344 - 40177
and 45701 - 47220 excluded due to the appearance in these regions of the
(111) and (200) Pt diffraction peaks of the sample holder The transmission
coefficient at the Pt(111) Bragg position is 035 which was used for correcting
the finite film thickness of the sample Number of contributing reflections is 86
No geometric restraints used Number of structural parameters is 7 Number of
profile parameters is 8 including unit cell parameters and zero shift (-0020ordm 2)
with visually estimated background (Average background = 38000 counts)
Profile function used was Pearson VII Refined overall thermal vibration
coefficient B = 60Aring2 The residuals of the refinement were Rwp=0026
Rp=0018 2=50
The Rietveld refinement of the pure silica-ITQ-29 data with LSP7 was
performed using the measured 2 range from 5ordm to 75ordm Number of contributing
20
reflections is 186 No geometric restraints used Number of structural
parameters is 7 Number of profile parameters is 8 including unit cell
parameters and zero shift (-0055ordm 2) with visually estimated background
(Average background = 400 counts) Profile function used was Pearson VII
Refined overall thermal vibration coefficient B = 07Aring2 The residuals of the
refinement were Rwp=0097 Rp=0062 RB=0032 2=28
21
5 Comparison of commercial LTA samples with ITQ-29 zeolites
The XRD patterns of different commercial LTA zeolites are given for
comparison purposes
Zeolite 3A is the potassium form of the LTA zeolite having the following
composition
06 K2O 040 Na2O 1 Al2O3 20 plusmn 01SiO2 x H2O
4A is the same zeolite but in the sodium its formula is
1 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
Finally 5A is the Ca2+ exchanged material with the following composition
080 CaO 020 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
(all of them were purchased from Aldrich Co)
As can be seen all the commercial LTA samples posses a framework SiAl ratio
close to 1
22
In the figure It can be seen there that the peak intensities greatly depend on the
nature of the exchanged cation located within the cavities of the LTA structure
Also the X-ray diffraction lines of pure silica ITQ-29 zeolite are shifted towards
low 2θ values (ie higher d spacing) due to the smaller ionic radii of Si than that
of Al However the formation of pure silica LTA can be unambiguously
confirmed from the absence of non assigned diffraction lines and the goodness
of Rietveld refinement
23
- SUPPLEMENTARY MATERIAL
-
Table 3 Fractional atomic coordinates[ab] for pure silica ITQ-29
Atom x y z No of positions
Wyckoff notation
Si 03683(3) 01847(3) 0 24 k
O1 12 02179(7) 0 12 h
O2 02939(7) x 0 12 i
O3 03429(4) 01098(7) y 24 m
[a] As obtained from Rietveld refinement (space group Pm3m a=118671(4)Aring)[b] Estimated standard deviations given in parentheses
Figure 4b Observed (crosses) and calculated (lines) XRD patterns of pure silica zeolite A as well as the difference profile (bottom) The short tick marks below the pattern give the positions of Bragg reflections (Cu K12 radiation) To emphasize the high angle portion of the pattern the first reflection has been cut at half height
The refined unit cell volume is shorter by 64 Aring3 than the volume found for
the Ge containing form (ie 1671 Aring3 in front of 1735 Aring3) This result is consistent
with the larger ionic radius of Ge compared to Si that is also responsible of the
larger averaged T-O distance obtained in the Ge zeolite (d(T-O)=162Aring) than in
18
the pure silica ITQ-29 material (d(Si-O)=160Aring) The averaged distance (d) and
angles ( ) from the tetrahedron are d(Si-O)=160Aring (O-Si-O) = 1094ordm (Si-
O-Si) = 1533ordm It is notorious (see Table 4) that the most tensioned Si-O-Si
angle is the Si-O2-Si angle (1584ordm) which correspond to the oxygen that is
linking to neighboured D4R cages On the other hand the Si-O-Si angles
corresponding to oxygen atoms placed at that small D4R cage do not seem to
be strongly constrained giving Si-O1-Si and Si-O3-Si angles of 1517 and
1497ordm respectively
Table 4 Bond distances in Aring and bond angles in (ordm) with esds in parentheses
for pure Si zeolite A
Si - O1 1612(5)Si - O2 1568(7)Si - O3 1606(7) (2x)O1 - Si - O2 1102(4)O1 - Si - O3 1085(5) (2x)O2 - Si - O3 1106(6) (2x)O3 - Si - O3 1085(7)Si - O1 -Si 1517(6)Si- O2 - Si 1584(9)Si - O3 - Si 1497(9)
The details of the Rietveld refinement are given in the Experimental Section
Experimental section
XRD
The Ge containing ITQ-29 sample was calcined at 700ordmC for 1 hour The
pattern was measured at room temperature in vacuum on a Philips XPert
diffractometer with Bragg-Brentano geometry using a Pt sample holder and an
19
XCelerator detector Intensity data obtained with fixed divergence slit (025ordm)
Cu K radiation ( = 15406 15444Aring) Tube voltage and intensity 45 kV and
40 mA Step size and time 0017ordm 2 and 6000s
The pure silica ITQ-29 sample was calcined at 700ordmC in air for 3 hours
The pattern was measured at room temperature on a Philips XPert
diffractometer with Bragg-Brentano geometry using a conventional flat stage
holder and an XCelerator detector Intensity data obtained with fixed
divergence slit (0125ordm) Cu K radiation ( = 15406 15444Aring) Tube voltage
and intensity 45 kV and 40 mA Step size and time 0017ordm 2 and 6000s
Rietveld refinement
The Rietveld refinement of Ge-ITQ-29 data was performed with LSP7
using a 2 range from 135ordm to 642ordm with the regions between 39344 - 40177
and 45701 - 47220 excluded due to the appearance in these regions of the
(111) and (200) Pt diffraction peaks of the sample holder The transmission
coefficient at the Pt(111) Bragg position is 035 which was used for correcting
the finite film thickness of the sample Number of contributing reflections is 86
No geometric restraints used Number of structural parameters is 7 Number of
profile parameters is 8 including unit cell parameters and zero shift (-0020ordm 2)
with visually estimated background (Average background = 38000 counts)
Profile function used was Pearson VII Refined overall thermal vibration
coefficient B = 60Aring2 The residuals of the refinement were Rwp=0026
Rp=0018 2=50
The Rietveld refinement of the pure silica-ITQ-29 data with LSP7 was
performed using the measured 2 range from 5ordm to 75ordm Number of contributing
20
reflections is 186 No geometric restraints used Number of structural
parameters is 7 Number of profile parameters is 8 including unit cell
parameters and zero shift (-0055ordm 2) with visually estimated background
(Average background = 400 counts) Profile function used was Pearson VII
Refined overall thermal vibration coefficient B = 07Aring2 The residuals of the
refinement were Rwp=0097 Rp=0062 RB=0032 2=28
21
5 Comparison of commercial LTA samples with ITQ-29 zeolites
The XRD patterns of different commercial LTA zeolites are given for
comparison purposes
Zeolite 3A is the potassium form of the LTA zeolite having the following
composition
06 K2O 040 Na2O 1 Al2O3 20 plusmn 01SiO2 x H2O
4A is the same zeolite but in the sodium its formula is
1 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
Finally 5A is the Ca2+ exchanged material with the following composition
080 CaO 020 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
(all of them were purchased from Aldrich Co)
As can be seen all the commercial LTA samples posses a framework SiAl ratio
close to 1
22
In the figure It can be seen there that the peak intensities greatly depend on the
nature of the exchanged cation located within the cavities of the LTA structure
Also the X-ray diffraction lines of pure silica ITQ-29 zeolite are shifted towards
low 2θ values (ie higher d spacing) due to the smaller ionic radii of Si than that
of Al However the formation of pure silica LTA can be unambiguously
confirmed from the absence of non assigned diffraction lines and the goodness
of Rietveld refinement
23
- SUPPLEMENTARY MATERIAL
-
the pure silica ITQ-29 material (d(Si-O)=160Aring) The averaged distance (d) and
angles ( ) from the tetrahedron are d(Si-O)=160Aring (O-Si-O) = 1094ordm (Si-
O-Si) = 1533ordm It is notorious (see Table 4) that the most tensioned Si-O-Si
angle is the Si-O2-Si angle (1584ordm) which correspond to the oxygen that is
linking to neighboured D4R cages On the other hand the Si-O-Si angles
corresponding to oxygen atoms placed at that small D4R cage do not seem to
be strongly constrained giving Si-O1-Si and Si-O3-Si angles of 1517 and
1497ordm respectively
Table 4 Bond distances in Aring and bond angles in (ordm) with esds in parentheses
for pure Si zeolite A
Si - O1 1612(5)Si - O2 1568(7)Si - O3 1606(7) (2x)O1 - Si - O2 1102(4)O1 - Si - O3 1085(5) (2x)O2 - Si - O3 1106(6) (2x)O3 - Si - O3 1085(7)Si - O1 -Si 1517(6)Si- O2 - Si 1584(9)Si - O3 - Si 1497(9)
The details of the Rietveld refinement are given in the Experimental Section
Experimental section
XRD
The Ge containing ITQ-29 sample was calcined at 700ordmC for 1 hour The
pattern was measured at room temperature in vacuum on a Philips XPert
diffractometer with Bragg-Brentano geometry using a Pt sample holder and an
19
XCelerator detector Intensity data obtained with fixed divergence slit (025ordm)
Cu K radiation ( = 15406 15444Aring) Tube voltage and intensity 45 kV and
40 mA Step size and time 0017ordm 2 and 6000s
The pure silica ITQ-29 sample was calcined at 700ordmC in air for 3 hours
The pattern was measured at room temperature on a Philips XPert
diffractometer with Bragg-Brentano geometry using a conventional flat stage
holder and an XCelerator detector Intensity data obtained with fixed
divergence slit (0125ordm) Cu K radiation ( = 15406 15444Aring) Tube voltage
and intensity 45 kV and 40 mA Step size and time 0017ordm 2 and 6000s
Rietveld refinement
The Rietveld refinement of Ge-ITQ-29 data was performed with LSP7
using a 2 range from 135ordm to 642ordm with the regions between 39344 - 40177
and 45701 - 47220 excluded due to the appearance in these regions of the
(111) and (200) Pt diffraction peaks of the sample holder The transmission
coefficient at the Pt(111) Bragg position is 035 which was used for correcting
the finite film thickness of the sample Number of contributing reflections is 86
No geometric restraints used Number of structural parameters is 7 Number of
profile parameters is 8 including unit cell parameters and zero shift (-0020ordm 2)
with visually estimated background (Average background = 38000 counts)
Profile function used was Pearson VII Refined overall thermal vibration
coefficient B = 60Aring2 The residuals of the refinement were Rwp=0026
Rp=0018 2=50
The Rietveld refinement of the pure silica-ITQ-29 data with LSP7 was
performed using the measured 2 range from 5ordm to 75ordm Number of contributing
20
reflections is 186 No geometric restraints used Number of structural
parameters is 7 Number of profile parameters is 8 including unit cell
parameters and zero shift (-0055ordm 2) with visually estimated background
(Average background = 400 counts) Profile function used was Pearson VII
Refined overall thermal vibration coefficient B = 07Aring2 The residuals of the
refinement were Rwp=0097 Rp=0062 RB=0032 2=28
21
5 Comparison of commercial LTA samples with ITQ-29 zeolites
The XRD patterns of different commercial LTA zeolites are given for
comparison purposes
Zeolite 3A is the potassium form of the LTA zeolite having the following
composition
06 K2O 040 Na2O 1 Al2O3 20 plusmn 01SiO2 x H2O
4A is the same zeolite but in the sodium its formula is
1 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
Finally 5A is the Ca2+ exchanged material with the following composition
080 CaO 020 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
(all of them were purchased from Aldrich Co)
As can be seen all the commercial LTA samples posses a framework SiAl ratio
close to 1
22
In the figure It can be seen there that the peak intensities greatly depend on the
nature of the exchanged cation located within the cavities of the LTA structure
Also the X-ray diffraction lines of pure silica ITQ-29 zeolite are shifted towards
low 2θ values (ie higher d spacing) due to the smaller ionic radii of Si than that
of Al However the formation of pure silica LTA can be unambiguously
confirmed from the absence of non assigned diffraction lines and the goodness
of Rietveld refinement
23
- SUPPLEMENTARY MATERIAL
-
XCelerator detector Intensity data obtained with fixed divergence slit (025ordm)
Cu K radiation ( = 15406 15444Aring) Tube voltage and intensity 45 kV and
40 mA Step size and time 0017ordm 2 and 6000s
The pure silica ITQ-29 sample was calcined at 700ordmC in air for 3 hours
The pattern was measured at room temperature on a Philips XPert
diffractometer with Bragg-Brentano geometry using a conventional flat stage
holder and an XCelerator detector Intensity data obtained with fixed
divergence slit (0125ordm) Cu K radiation ( = 15406 15444Aring) Tube voltage
and intensity 45 kV and 40 mA Step size and time 0017ordm 2 and 6000s
Rietveld refinement
The Rietveld refinement of Ge-ITQ-29 data was performed with LSP7
using a 2 range from 135ordm to 642ordm with the regions between 39344 - 40177
and 45701 - 47220 excluded due to the appearance in these regions of the
(111) and (200) Pt diffraction peaks of the sample holder The transmission
coefficient at the Pt(111) Bragg position is 035 which was used for correcting
the finite film thickness of the sample Number of contributing reflections is 86
No geometric restraints used Number of structural parameters is 7 Number of
profile parameters is 8 including unit cell parameters and zero shift (-0020ordm 2)
with visually estimated background (Average background = 38000 counts)
Profile function used was Pearson VII Refined overall thermal vibration
coefficient B = 60Aring2 The residuals of the refinement were Rwp=0026
Rp=0018 2=50
The Rietveld refinement of the pure silica-ITQ-29 data with LSP7 was
performed using the measured 2 range from 5ordm to 75ordm Number of contributing
20
reflections is 186 No geometric restraints used Number of structural
parameters is 7 Number of profile parameters is 8 including unit cell
parameters and zero shift (-0055ordm 2) with visually estimated background
(Average background = 400 counts) Profile function used was Pearson VII
Refined overall thermal vibration coefficient B = 07Aring2 The residuals of the
refinement were Rwp=0097 Rp=0062 RB=0032 2=28
21
5 Comparison of commercial LTA samples with ITQ-29 zeolites
The XRD patterns of different commercial LTA zeolites are given for
comparison purposes
Zeolite 3A is the potassium form of the LTA zeolite having the following
composition
06 K2O 040 Na2O 1 Al2O3 20 plusmn 01SiO2 x H2O
4A is the same zeolite but in the sodium its formula is
1 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
Finally 5A is the Ca2+ exchanged material with the following composition
080 CaO 020 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
(all of them were purchased from Aldrich Co)
As can be seen all the commercial LTA samples posses a framework SiAl ratio
close to 1
22
In the figure It can be seen there that the peak intensities greatly depend on the
nature of the exchanged cation located within the cavities of the LTA structure
Also the X-ray diffraction lines of pure silica ITQ-29 zeolite are shifted towards
low 2θ values (ie higher d spacing) due to the smaller ionic radii of Si than that
of Al However the formation of pure silica LTA can be unambiguously
confirmed from the absence of non assigned diffraction lines and the goodness
of Rietveld refinement
23
- SUPPLEMENTARY MATERIAL
-
reflections is 186 No geometric restraints used Number of structural
parameters is 7 Number of profile parameters is 8 including unit cell
parameters and zero shift (-0055ordm 2) with visually estimated background
(Average background = 400 counts) Profile function used was Pearson VII
Refined overall thermal vibration coefficient B = 07Aring2 The residuals of the
refinement were Rwp=0097 Rp=0062 RB=0032 2=28
21
5 Comparison of commercial LTA samples with ITQ-29 zeolites
The XRD patterns of different commercial LTA zeolites are given for
comparison purposes
Zeolite 3A is the potassium form of the LTA zeolite having the following
composition
06 K2O 040 Na2O 1 Al2O3 20 plusmn 01SiO2 x H2O
4A is the same zeolite but in the sodium its formula is
1 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
Finally 5A is the Ca2+ exchanged material with the following composition
080 CaO 020 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
(all of them were purchased from Aldrich Co)
As can be seen all the commercial LTA samples posses a framework SiAl ratio
close to 1
22
In the figure It can be seen there that the peak intensities greatly depend on the
nature of the exchanged cation located within the cavities of the LTA structure
Also the X-ray diffraction lines of pure silica ITQ-29 zeolite are shifted towards
low 2θ values (ie higher d spacing) due to the smaller ionic radii of Si than that
of Al However the formation of pure silica LTA can be unambiguously
confirmed from the absence of non assigned diffraction lines and the goodness
of Rietveld refinement
23
- SUPPLEMENTARY MATERIAL
-
5 Comparison of commercial LTA samples with ITQ-29 zeolites
The XRD patterns of different commercial LTA zeolites are given for
comparison purposes
Zeolite 3A is the potassium form of the LTA zeolite having the following
composition
06 K2O 040 Na2O 1 Al2O3 20 plusmn 01SiO2 x H2O
4A is the same zeolite but in the sodium its formula is
1 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
Finally 5A is the Ca2+ exchanged material with the following composition
080 CaO 020 Na2O 1 Al2O3 20 plusmn 01 SiO2 x H2O
(all of them were purchased from Aldrich Co)
As can be seen all the commercial LTA samples posses a framework SiAl ratio
close to 1
22
In the figure It can be seen there that the peak intensities greatly depend on the
nature of the exchanged cation located within the cavities of the LTA structure
Also the X-ray diffraction lines of pure silica ITQ-29 zeolite are shifted towards
low 2θ values (ie higher d spacing) due to the smaller ionic radii of Si than that
of Al However the formation of pure silica LTA can be unambiguously
confirmed from the absence of non assigned diffraction lines and the goodness
of Rietveld refinement
23
- SUPPLEMENTARY MATERIAL
-
In the figure It can be seen there that the peak intensities greatly depend on the
nature of the exchanged cation located within the cavities of the LTA structure
Also the X-ray diffraction lines of pure silica ITQ-29 zeolite are shifted towards
low 2θ values (ie higher d spacing) due to the smaller ionic radii of Si than that
of Al However the formation of pure silica LTA can be unambiguously
confirmed from the absence of non assigned diffraction lines and the goodness
of Rietveld refinement
23
- SUPPLEMENTARY MATERIAL
-