crystal structure and physicochemical properties of a new.pdf

7/28/2019 Crystal Structure and Physicochemical Properties of a New.pdf

1/5

C O M M U N I C A T I O N

Crystal Structure and Physicochemical Properties of a New4,40-Diammoniumdiphenylether Triphosphate

[C12H14N2O]2HP3O102H2O

Saloua Belghith Latifa Ben Hamada

Amor Jouini

Received: 23 July 2012 / Accepted: 18 January 2013 Springer Science+Business Media New York 2013

Abstract Crystals of 4,40-diammoniumdiphenylether tri-

phosphate, [C12H14N2O]2HP3O102H2O (1), were preparedand grown at room temperature. Species 1 crystallizes in

the triclinic system with centric space group P1. Its unit

cell dimensions are a = 10.487(2), b = 10.766(2), c =

15.553(2) A, a = 98.53(1), b = 107.55(1), c = 103.31(2),

with V= 1588.8(5) A3 and Z= 2. The structure was deter-

mined by X-ray data collection on a single-crystal and gives

a clear description of hydrogen bonds interconnecting the

triphosphoric groups so as to build [(HP3O10)2(H2O)]8-

infinite inorganic chains that extend along the [110] direc-

tion. Organic cations, spreading along the [101] direction

establish hydrogen bonding connections between the inor-

ganic chains. The IR spectrum for the crystal confirms that

most of the vibrational modes are comparable to similar

triphosphates. The thermal properties reveal that the com-

pound is stable to 90 C.

Keywords Crystal structure Thermal behavior Infraredspectroscopy 4,40-Diammoniumdiphenylethertriphosphate

1 Introduction

Oligophosphates are the simplest term for condensed phos-

phates. Their anions correspond to the general formula

[PnO3n?1]

(n?2)-. The triphosphates (n = 3) were mainly

studied with mineral cations. However, several organic

compounds with acidic triphosphoric anions; e.g.

[HP3O104-], [H2P3O103-], [H3P3O102-] and [H4P3O10-],have been reported. Four examples include [C4N2H12]2HP3O10H2O [1], [3,5-CH3O)2C6H3NH3]3H2P3O10 [2],[2,6-(C6H5)2C6H3NH3]2H3P3O10 [3],[4(CH3O)C6H4CH2NH3]4 and H2P3O10H4P3O10 [4]. These acidic anions

reveal the flexibility of their aggregation, via H-bonds, with

respect to the organic cations inducing various geometries:

chains, ribbons, layers and three-dimensional networks.

Many combinations between organic and inorganic com-

ponents may be achieved to create materials in several

areas; e.g. sorbents, catalysts and biotechnological mate-

rials [5, 6], because of the nature (molecular, ionic,

hydrogen bonding) [7] of the interaction between them. As

a contribution to the study of organic triphosphate com-

pounds, we report here the preparation and structural

investigation of a new 4,40-diammoniumdiphenylether tri-

phosphate dihydrate, [C12H14N2O]2HP3O102H2O (1). Thethermal behavior (TGA/DTA, DSC) and IR spectrum of1

were also examined.

2 Experimental

2.1 Preparation of1

Sodium tripolyphosphate Na5P3O10 [8] was prepared by

heating a stoichiometric mixture of disodium phosphate,

Na2HPO4 (0.2 mol, 6 g), and monosodium phosphate,

NaH2PO4 (0.1 mol, 2.53 g) at 200 C under carefully

controlled conditions (Eq. 1).

2Na2HPO4 NaH2PO4 ! Na5P3O10 2H2O 1

After the preparation and identification of Na5P3O10, the

salt was used as a starting material to synthesize the organic

S. Belghith (&) L. B. Hamada A. JouiniLaboratoire de Chimie du Solide, Departement de chimie,

Faculte des Sciences de Monastir, Universite du centre, 5019

Monastir, Tunisia

e-mail: [email protected]

123

J Inorg Organomet Polym

DOI 10.1007/s10904-013-9831-z


2/5

triphosphate. Single crystals of1 were prepared in two steps;

(i) An aqueous solution of triphosphoric acid is first obtained

by passing a solution of Na5P3O10 (4.13 g) through an ion

exchange resin (Amberlite IR 120). (ii) 4,40-

diaminodiphenylether (4 g) was added to the solution

(Eq. 2).

H5P3O10 2C12H12N2O !

H2O

C12H14N2O2HP3O102H2O2

When most of the solvent (pH= 2) was evaporated,

prismatic crystals appear. The crystals were pure and stable

under normal conditions of temperature and humidity.

2.2 X-ray Structure Determination of1

X-ray intensity data were collected on a Nonius-Mach 3

diffractometer using monochromatic MoKa

radiation. The

results are summarized in Table 1. The structure was

solved by direct method using the SHELXS-97 programs,

which allows the location of the P3O10 groups. The

remaining non-hydrogen atoms were found by the suc-

cessive difference Fourier maps using the SHELXL-97

programs [9]. In the final least-squares refinement of

atomic parameters with isotropic thermal factors of

H-atoms, R decreased to 3.61 % (Rw = 9.34 %) for 1. It

should be noted that one H-atom of O(W2) was not

included in the refinement since its corresponding O-atom

has a higher thermal coefficient.

2.3 Thermal Behavior of 1

A Setaram TGDTA92 and a DSC1 star system MettlerToledo thermoanalyser were used to perform thermal

treatment on 1. The TGDTA experiments were carried out

with 16.6 mg samples in an open alumina crucible. The

DSC analyses were made with 7.4 mg (on heating) and

7.5 mg (on heating and cooling) samples sealed in alumi-

num DSC crucibles. In both techniques, the samples were

heated in air at a heating rate of 5 C min-1.

2.4 Infrared Spectroscopy

The IR spectrum of 1 was recorded at room temperature

with a Biored FTS 6000 FTIR spectrometer from 4,000 to400 cm-1 with a resolution of*4 cm-1. Thin transparent

pellets were made by compacting an intimate mixture

obtained by shaking 2 mg of the samples in 100 mg of

KBr.

3 Results and Discussion

3.1 Structure Description of 1

The asymmetric unit of1 contains two organic cations, one

monohydrogentriphosphate anion and two water mole-

cules. The atomic arrangement can be described as inor-

ganic chains built by HP3O104- anions and one water

molecule. In such a chain, two HP3O104- anions are linked

together by strong OHO hydrogen bonds to form

H2P6O208- cyclic units. An OD(donor)OA(acceptor)

distance of 2.553(3) A is the same order of magnitude as

the PO4 tetrahedron. Each one of these units is connected

by (OW1) to its two neighbours by hydrogen bonds,

ODLOA = 2.829(4)2.890(4) A, to form infinite chains

parallel to the [110] direction (Fig. 1). The HP3O104- anion

has no internal symmetry; therefore, it is built from three

independent PO4 tetrahedrons. Nevertheless some of the

known triphosphate anions with mineral cations have a

twofold internal symmetry, their central phosphorous being

located on a twofold axis [1014]. There are three different

types of PO distances inside the PO4 tetrahedron; i.e. the

longest [1.607(2) and 1.631(2) A] corresponds to the

bridging oxygen atoms. The intermediate [1.554(2) A]

corresponds to the POH bonding and the shortest, which

is between 1.480(2) A and 1.512(2) A (relative to the

external O-atoms). Despite these differences, the average

Table 1 Crystallographic data and refinement details for 1

Empirical formula [C12H14N2O]2HP3O102H2O

Formula weight (g mol-1) 694.45

Temperature (K) 293

Wavelength (A) 0.71073

Space group P1(2)

Unit cell dimension

a (A) 10.487(2)

b (A) 10.766(2)

c (A) 15.553(2)

a () 98.53(1)

b () 107.55(1)

c () 103.31(2)

Cell volume (A3) 1588.8(5)

Z 2

Absorption coefficient (mm-1) 0.260

Crystal size (mm3) 0,43 9 0,41 9 0,18

h range for data collection () 225

Reflections (collected/unique) 6254/5522 [R(int) = 0.0194]

Parameters 543

Goodness-of-fit 1.015

R indices [I[2r(I)] R1 = 0.0361, wR2 = 0.0934

R indices (all data) R1 = 0.0594, wR2 = 0.1047

Dqmax/Dqmin (e.A-3) 0.294/ -0.278


123


3/5

values for the PO distances (1.538 A) and OPO angles

(109.28) (Table 2) indicate that the PO4 regular a tetra-

hedron. Organic cations, inducing NHO hydrogenbonds, are oriented along [101] direction to ensure struc-

tural stability (Fig. 2).

The two types of hydrogen bonds, OHO and NHO,contribute to the cohesion in the network of 1. Figure 3

shows the hydrogen bonds in an asymmetric unit of 1.

Moreover, the four aromatic rings built up by the six car-

bon atoms, C1 ? C6 (AR1), C7 ? C12 (AR2),

C13 ? C18 (AR3) and C19 ? C24 (AR4), are relatively

planar with r.m.s. deviations of the six C-atoms of each

ring from their restraint planes of 0.0058 A (AR1),

0.0027 A (AR2), 0.0033 A (AR3) and 0.0116 A (AR4).

Their dihedral angles \AR1, AR2; \AR1, AR3,\AR1,

AR4, \AR2, AR3, \AR2, AR4 and \AR3, AR4 being,respectively, 65.24(2), 36.38(1), 46.58(2), 80.74(2),

43.23(1)and 80.49(2), and indicate that these two inde-

pendent organic cations do not have the same orientation

within this crystal structure; their behaviour is rather dif-

ferent. Indeed, the central O-atom of one of is disordered

and must be described as two fragments with occupancy

rates of O(2A)0.57 O(2B)0.43 (Fig. 4), with dO(2A)O(2B) =

0.989(9) A.

Fig. 1 Infinite chains of HP3O104-.2H2O viewed down the crystallo-

graphic c axis

Table 2 Main interatomic distances (A) and bond angles () in the

PO4

tetrahedra of 1

P(1) O(E11) O(E12) O(E13) O(L12)

O(E11) 1.490(2) 107.87(10) 118.14(10) 109.91(9)

O(E12) 2.461(1) 1.554(2) 111.29(10) 105.53(10)

O(E13) 2.562(3) 2.519(3) 1.497(2) 103.37(9)

O(L12) 2.536(3) 2.517(3) 2.436(3) 1.607(2)

P(2) O(E21) O(E22) O(L12) O(L23)

O(E21) 1.483(2) 117.82(10) 109.02(9) 107.86(9)

O(E22) 2.537(3) 1.480(2) 110.01(10) 111.42(9)

O(L12) 2.515(3) 2.526(3) 1.605(2) 99.04(9)

O(L23) 2.485(3) 2.538(3) 2.431(2) 1.591(2)

P(3) O(E31) O(E32) O(E33) O(L23)

O(E31) 1.504(2) 114.22(11) 112.28(10) 102.53(9)

O(E32) 2.526(3) 1.505(2) 113.26(10) 106.70(9)

O(E33) 2.504(3) 2.519(2) 1.512(2) 106.81(9)

O(L23) 2.446(3) 2.517(3) 2.524(3) 1.631(2)

P(1)P(2) 2.934(1) P(1)O(L12)P(2) 132.0(2)

P(2)P(3) 2.916(1) P(2)O(L23)P(3) 129.6(2)

P(1)O(E12)H12 112(2)

Fig. 2 Projection along the b axis of the atomic arrangement in 1

Fig. 3 Hydrogen bonds in an asymmetric unit of 1


123


4/5

3.2 Thermal Behaviour

The TGDTA thermogram of 1 (Fig. 5) was obtained on

ground samples. The TG curve shows that this compound

is stable to 90 C. The removal of the two water molecules

(weight loss = 0.3 mg) from 94 to 170 C is related to the

endothermic DTA peak with maximum elimination at

119 C. This dehydration occurs in a large temperature

domain and indicates the presence of two types of water

molecules. Indeed, the structural resolution shows that one

water molecule is less restrained in the atomic arrange-

ment. The exothermic peak at 150 C is probably due to

the enhanced partial pressure of water vapour. Furthermore

the DTA curve reveals two endothermic peaks at 194 and

220 C and indicates the presence of two phase transitions

since the TG curve does not show any weight loss. With afurther increase in temperature, the sample decomposes

(230350 C) with maximum evolution of ammonia at

268 C. Ammonia is indicated by its odor. Indeed the TG

curve shows a rather substantial and continuous weight loss

during the second phase transition. The base line, as shown

in the DTA curve, is gently sloping downward and its slope

may change with temperature. Such a premonitory

phenomenon is associated with an increase of atomic

motions; in particular the increase of disorder when thedecomposition is approached.

On the other hand, the DSC thermogram for ground

samples (Fig. 6) exhibits the same thermal behaviour as the

DTA. Nevertheless, endothermic effects are somewhat

shifted to lower temperature since the two techniques (TG

DTA and DSC) have different sensitivities. The first

endotherm corresponds to dehydration with DHde-

hyd = 32.4 kJ mol-1; the two following endotherms at 188

and 216 C have DH(P.T1) = 8.3 kJ mol-1 and

DH(P.T2) = 0.95 kJ mol-1, respectively, and are related to

two phase transitions. A cycle of heating and cooling, with

equal rate (5 C min-1) from room temperature to 223 C

(Fig. 7) confirms the presence of the phase transitions.

Nevertheless, the absence of exothermic peaks on cooling

indicates that the transformation is irreversible.

3.3 IR Spectroscopic Investigation

The IR spectrum of crystalline 4,40-diammoniumdipheny-

lether triphosphate is shown in Fig. 8. Representative and

characteristic vibrational modes for the compound are

Fig. 4 Representation of the organic cations in 1

Fig. 5 TG-DTA thermogram of 1

Fig. 6 DSC thermogram of 1

Fig. 7 Cycle of heating and cooling of 1


123


5/5

compared to similar triphosphates [14]; i.e. (O3POPO2

OPO3). The assignments are as follows:

The stretching vibrations of PO2 central group are

observed between 1300 and 1100 cm-1. Those between

1260 and 990 cm-1 correspond to the stretching

vibrations of PO3 terminal groups. Those ranging from

670 to 960 cm-1 correspond to the stretching POP

modes [15, 16]. The bending vibrations of PO3 terminal

groups are from 600 to 400 cm-1. Supplementary

frequencies in the m(PO3) domain are attributed to the

bending modes, d(CaryH) and d(CaryCary) [17].

Bands from 1600 to 1200 cm-1 correspond to the

bending vibrations of NH and OH groups. The

valence vibrations of CC and CN groups occur in this

same region.

Bands from 3600 to 2300 cm-1 are attributed to the

stretching of the organic and hydroxyl groups, m(NH),

m(CH) and m(OH) of H2O and POH groups.

4 Conclusions

Compound 1 was prepared as a single crystal at room tem-

perature. The physicochemical characterization of1 using

TG-DTA, DSC and IR are reported. The atomic arrangement

in 1 is described by chains of HP3O104- groups and water

molecules that are parallel to the [110] direction. The inter-layer spacing is occupied by the organic entities extended

along the [101] direction and assembled as inorganic chains

giving rise to a three-dimensional network, which can be

designed by an alternative localization of mineral and

organic entities. The gap between the average planes of the

mineral and the organic cations is approximately 7.8 A and

correspond to half the c parameter. 1 is stable to 90 C and

then undergoes a dehydration and degradation of the organic

entity. The thermal behavior of1 reveals two-phase transi-

tions; thermodynamic properties were deduced from the

calorimetry. The same thermal behaviour was confirmed by

the DSC. The energies of the crystals vibration modes wereassigned on the basis of the characteristic vibrations of the

POP, PO2 and PO3 groups.

5 Supporting Data

Crystallographic data for the structural analysis have been

deposited at the Cambridge Crystallographic Data Centre,

CCDC No 818074. Copies of this information may be

obtained free of charge from The Director, CCDC, 12

Union Road, Cambridge, CB2 IEZ, UK(fax: ?44-1226-

336033; e-mail: [email protected]).

References

1. W. Smirani, C. Ben Nasr, M. Rzaigui, Phosphorus Sulfur Silicon

179, 2195 (2004)

2. W. Smirani, M. Rzaigui, Z. Kristallorg, NCS 220, 250 (2005)

3. W. Smirani, M. Rzaigui, Phosphorus Sulfur Silicon 182, 2195

(2007)

4. W. Smirani, M. Rzaigui, Anal. Sci. 21, 109 (2005)

5. R.C. Finn, J. Zubieta, R.C. Hanshalter, Prog. Inorg. Chem. 51,

451 (2002)

6. B. Koo, W. Ollette, E.M. Burkholder, V. Golub, C.J. Oconnor,

J. Zubieta, J. Solid State Sci. 6, 461 (2004)

7. F. Neve, A. Crispini, O. Frances Cangelie, Inorg. Chem. 39, 1187

(2000)

8. G.W. Morey, E. Ingerson, Am. J. Sci. 1, 242 (1944)

9. G.M. Sheldrick, Acta Cryst. A64, 112 (2008)

10. D.E.C. Corbridge, Acta. Cryst. 13, 263 (1960)

11. D.K. Davies, D.E.C. Corbridge, Acta. Cryst. 11, 315 (1958)

12. E.A. Prodan, B.M. Galogadja, P.N. Petruskaia, B.H. Kordjev,

Dokl. Akad. Nauk SSSR 25, 163 (1981)

13. M.T. Averbuch-Pouchot, A. Durif, J. Coing-Boyat, J.C. Guitel,

Acta Cryst. B33, 203 (1977)

14. V.V. Krasnikov, Z.A. Konstant, V.S. Fundamenskii, Izv. Akad.

Nauk SSSR. Neorg. Mater. 19, 1373 (1983)

15. R.W. Mooney, S.Z. Toma, J. Brunvoll, Spectrochim. Acta A2,

1541 (1967)

16. B.C. Cornilson, J. Mol. Struct. 117, 1 (1984)

17. R.M. Silverstein, G.C. Basler, T.C. Morill, Spectrometric Iden-

tification of Organic Compounds 3rd ed (Wiley, New York,

1974)

Fig. 8 IR Spectrum of 1


123

crystal structure and physicochemical properties of a new.pdf

Documents