How How molecules molecules go go magnetic magnetic ……
Michel Michel VerdaguerVerdaguer, Françoise , Françoise VillainVillain,,Ruxandra GheorgheRuxandra Gheorghe, Fabrice , Fabrice PointillartPointillart
Université Pierre et Marie Curie, Paris
A lecture A lecture proposed proposed byby
SPP SPP Molekular Magnetismus Molekular Magnetismus (DFG)(DFG)
Why experimentsexperiments ?
because …
- experiment arises curiosity- experiment is speaking …- experiment is demonstrating …- experiment can be beautiful !
Bad Durkheim, SPP Molecular Magnetismus (DFG) 6-9 may 2007
Why experiments in magnetismmagnetism ?
because …
- it is an important phenomenon …- it arises curiosity …- it needs to be demystified and explained- and experiments are beautiful !
Why experiments in molecular magnetismmolecular magnetism ?
because …
- our live relies on it and nobody knows …- it is badly known or unknown … - it can be explained simply …- and experiments are beautiful !
Goals ?
1) Citizen awareness 2) Attract good students to our discipline
3) Here : convincing you that such experiments are possible to realize during Science Festivals ..
LECTURELECTURE
Bad Durkheim, SPP Molecular Magnetismus (DFG) 6-9 may 2007
((abridged abridged ……))
Comments Comments about a possible about a possible ……
Publicity CampaignPublicity Campaign, , BarcelonaBarcelona, 2004 , 2004
or not ?
This is NOT
the question
Everything is magnetic Everything is magnetic
…… How ? How ?
Pierre CuriePierre CurieLectures NotesLectures Notes
Fonds documentaire ESPCIFonds documentaire ESPCI
Everything is magnetic Everything is magnetic ……
…… How ? How ?
Everything is magnetic Everything is magnetic ……
…… How ? How ?
Pierre CuriePierre CurieAnnales de ChimieAnnales de Chimie
77ème série, V, 1895, 289ème série, V, 1895, 289(Thèse de P. Curie)(Thèse de P. Curie)
Fonds documentaire ESPCIFonds documentaire ESPCI
Diamagnetic
Paramagnetic
Magnet
macroscopicworld
atomic ormolecular
world
« wonder »world
quantummacro
Cais do Sodre Metro Station Lisboa, Antonio Dacosta
Everyday lifeis full of useful magnets
which traditionally take the formof three-dimensional solids,
oxides, metals and alloys
Magnets in our world
We are in a real world, at our size
Courtesy Prof. Frank James, the RI
M. FaradayM. Faraday
A pioneering experimentby M. Faraday
« Faraday lines of forces » about magnetic flux
macroscopic world
Courtesy Prof. Peter Day, the RI ; See also :The Philosopher’s Tree,The Institute of Physics Publishing, Bristol, 19999
N
S
N
S
« Lines of field »
A magnet creates a magnetic field
What is a magnet ? What is NOT a magnet ?
macro
Magnetization
Applied magneticField H
Magnet
macroMagnetization : How behave objectsin a magnetic field ?
Magnetization M(how do they become « magnetized »?)Remnant Magnetization
CoerciveField
« hard »
Tout Tout est magnétique est magnétique
…… Comment ? Comment ?
Pierre CuriePierre CurieAnnales de ChimieAnnales de Chimie
77ème série, V, 1895, 289ème série, V, 1895, 289(Thèse de P. Curie)(Thèse de P. Curie)
Fonds documentaire ESPCIFonds documentaire ESPCI
Everyday lifeis full of useful magnets
which traditionally take the formof three-dimensional solids,
oxides, metals and alloys
macro
Curie Temperature
The magnetic moments order at Curie temperature
… Paramagnetic solid :thermal agitation (kT) largerthan the interaction (J)between molecules
Solid, Magnetically Orderedthermal agitation (kT) weaker than the interaction (J) between molecules
A set of molecules / atoms :
kT << J kT >> J
TC
kT ≈ J
Magnetic OrderTemperature
or CurieTemperature
Magnetic ordering : Curie Temperature …
… a demonstrator
from macroscopic to atomic world
S
Nmany sets of
« domains »≡ ≡ ≡
many sets of≡
atomic magneticmoments
looking closer to smaller and smaller magnets
N
S
macro
Domains
How magnets behave ?
Domains
S = 1020
1010
108 10
6 10
5 10
4 10
3 10
2 10 1
clusters individualspins
molecularclustersnanoparticlesmicron
particlespermanentmagnets
Physics : Macroscopic Mesoscopic Nanoscopic
-1
0
1
-40 -20 0 20 40
M/M
S
µ0H(mT)
multi - domainnucleation, propagation andannihilation of domain walls
-1
0
1
-100 0 100
M/M
S
µ0H(mT)
single - domainuniform rotation
curling
-1
0
1
-1 0 1
M/M
S
µ0H(T)
Fe8
1K0.1K
0.7K
magnetic momentquantum tunneling,
quantizationquantum interference
Wolfgang Wernsdorfer, Grenoble
macro quantum
Everyday lifeis full of useful magnets
CompassesMagneticEarth
1600William Gilbert
De Magnete
Jan van der Straet (Giovanni Stradanus), Bruges, 1523 ; Florence, 1605Nova Reperta, vers 1620-1630 , 14 planches gravées par Jérôme Wierix at Adriaen Collaert,éditées par Philippe Galle
Calcul de la longitude, Burin 22 x 28 cm around 1600 Inv. n° 11786
Compasses, Jiangomen station, Beijing
The fascination ofmagnets on children
«« A A wonder wonder of of such such nature I nature I experience experience as a as a child child of 4 orof 4 or5 5 yearsyears, , when my father showed when my father showed me a me a compasscompass. . That thisThat thisneedle behaved needle behaved in in such such a a determined way did determined way did not not at at all fitall fitinto the into the nature of nature of events which could find events which could find a place in a place in thetheunconscious unconscious world of concepts (world of concepts (effects connected witheffects connected withdirect «direct « touchtouch »). I »). I can still remember can still remember –– or or at at least least believebelieveI I can remember can remember –– that that this experience this experience made a made a deep anddeep andlasting impression lasting impression upon upon meme..Something deeply hidden had Something deeply hidden had to to be behind thingsbe behind things.. » »
A. EinsteinA. EinsteinQuoted by Livingston, J. D. In Driving Force: The Natural Magic of Magnets. Cambridge, MA: Harvard University Press, 1996. ISBN: 0674216458.
Everyday lifeis full of useful magnets
macro
Toys
Everything is magnetic Everything is magnetic
…… thanks thanks to to electrons electrons ……
Origin of Magnetism … the electron *
I am an electron
• rest mass me, • charge e-, • magnetic moment µB
everything, tiny, elementaryquantum
* but do not forget nuclear magnetism !
Origin of Magnetism
e-
« Orbital » magnetic moment « Intrinsic » magnetic moment
due to the spin
quantum
µspin = gs x µB x s ≈ µB
s = ± 1/2
µorbital = gl x µB x l
µtotal = µorbital + µspin
µorbital
µspin
(E'+e! ) " = [1
2m (p +
e
cA )2 +
eh
2mc #•$ % A-
p4
8m3c
2 &
eh2
8m2c
2$•$! &
eh
4m2c
2#•$! % p ]"
Dirac Equation
http://www-history.mcs.st-and.ac.uk/history/PictDisplay/Dirac.html
19281905
Nobel Prize 1933The Principles of Quantum Mechanics, 1930
ReprRepreesentations, sentations, Mod Modeels,ls,
Analogies Analogies ……
About About what what are are we speaking we speaking ??
Paul Klee, Théorie de l’art, Denoël, Paris
An isolated spin …
AnalogyAnalogy : : spin and arrow
Electron : corpuscle and wave
Wave functionΨ
Hokusai, the great wave in Kanagawa
Ψ+
Ψ−
l = 0 1 2 3
x,y,z
y,z,x
x
y zy
x
x y z
sp
d
angular representation
Electron : corpuscle and wave
Wave function or « orbital » Ψn, l, ml …
quantum
Vacant, empty
Orbitals
Doubly occupiedNO MORE than TWO !
Energy
Singly occupied
Electron : also an energy level
quantum
Energy Diagramme (« ladder »)
Principle 1 : fill from the bottom (aufbau)
!*
Nitrogen oxide NO•
C
N NO•O
R
•
!*
O ONN C
Nitronylnitroxyde
Electron : orbital and spin !
Singly occupied
Up
Down
« Paramagnetic »mS = ± 1/2
quantum
Electron : orbital and spin !
Doublyoccupied
S = 1/2 - 1/2 = 0 « Diamagnetic »
quantum
Principle 2 : no more than TWOelectrons per level (orbital)
with different spins !(Pauli’s exclusion principle)
DiamagneticSpin S = 0
quantum
Moleculesare most often regarded
as isolated, non magnetic, creatures
Dihydrogen
macro
N2 Diamagnetic
Pouring liquid dinitrogen
liquid dinitrogendoes NOT stick
diamagnetic
the dinitrogenis a diamagnetic molecule
px py pz
NAEN-N NB
diamagnetic, spin S = 0
All electrons are paired in bonds, very stable molecule
macro
when dioxygen is in its ground stateit is a triplet (spin S=1)
and its reactivity is weak
Paramagnetic O2
Liquid O2
liquid dioxygenliquid dioxygendoes does stickstick
OO22 is paramagneticis paramagnetic
the dioxygenthat we continuously breathe
is a magnetic molecule
px py pz
OAE
O-O OB
paramagnetic, spin S =1
Two of its electrons have parallel magnetic moments that shapes aerobic life and allows our existence as human beings
orthogonal πmolecular orbitals
when dioxygen is in an excited stateit can becomes a singlet (spin S=0)
and strange reactivity appearssometines useful (glow-worm …)
Singlet dioxygenquantum
Luminol Light
macro
dioxygen singlet (spin S=0)
glow-worm …
Documents from Nassau and Alvarez
luminol
NH
NH
O
OHNH2
N
N
O
OHNH2
OO
quantum
More complex molecular frameworkscalled metal complexesbuilt from transition metal and moleculesare able to bear up to five or seven electronswith aligned magnetic moments (spins)
H He
Li B N NeOC FBe
s Elements
d Elements : transition
p Elements
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
f Elements•
Ce
K
Rb
Fr
Cs
Na Mg
Ca
Sr
Ba
Ra
Al P ClSi S Ar
AsGe
In Sb
Bi
Sn
Se Kr
Xe
RnAt
Br
Te
PoPb
I
Nd LuYbPr Sm TmErPm Eu HoDyTbGd
Th LrNoMdPa NpU Pu CmAm Bk FmEsCf
Ac
Sc
Y
La
44,956
88,906
138,91
21
39
57
Ti
Zr
Hf
47,867
91,224
178,49
22
40
72
V
Nb
Ta
50,942
92,906
180,95
23
41
73
Cr
Mo
W
51,996
95,94
183,84
24
42
74
Mn
Tc
Re
54,938
98,906
186,21
25
43
75
Fe
Ru
Os
55,845
101,07
190,23
26
44
76
Co
Rh
Ir
58,933
102,91
192,22
27
45
77
Ni
Pd
Pt
58,693
106,42
195,08
28
46
78
Cu
Ag
Au
63,546
107,87
196,97
29
47
79
Zn
Cd
Hg
65,39
112,41
200,59
30
48
80
VSc Cr Mn Fe ZnCuNiCoTi
Y
La
Zr Mo Ru Pd CdAgRhTcNb
Hf W Os HgAuIrReTa•
Ga
TlPt
Il sistema periodico … (Primo Levi)
È bello raccontare i guai passati …
E5 d orbitals
Partial Ocupancy
Paramagnetism
Conductivity
x2-y2 z2 yzxz xy
z
xy
Unpaired Electrons
Transition Elements
quantum
PuigcerdaPuigcerda, , CerdanyaCerdanya, , may may 31, 200631, 2006
ML
z
y
x
LL
L
L
L
Mononuclear complex ML6
E
Splitting of the energy levels
Electrons Electrons …… WANTED ! WANTED !
An indirect manifestationAn indirect manifestationof of the presence the presence ofofunpairedunpaired electrons electrons ::the colourthe colour
Complexes of transition metal ions often display beautiful coloursessentially to d levels splitting
Colours in waterGeometrical Changes
Spin Changes
hν
The complexes of transition metal present often delicate and beautiful coloursdepending mostly on the splitting of the d orbitals
hνhν
quantum macro
hν hνhνhν
Complexes of transition metal ions often display beautiful coloursessentially to d levels splitting
Colours in waterGeometrical Changes
Spin Changes
∆S ≠ 0
quantum macro
Electrons Electrons …… WANTED ! WANTED !
A A direct direct manifestationmanifestationof of the presence the presence ofofunpairedunpaired electronselectrons ::the magnetismthe magnetismor interaction or interaction with with a a magnmagneetic fieldtic field
How large is the splitting ?
!oct
y
x
z
z2x2-y2
y
x
z
x
z
y
xy xz yz
t2g
eg
High spin
L = H2O[C2O4]2-
Low spin
L = CN-
?
Weak Field Strong FieldIntermediate Field
TemperatureDependent
Spin Cross-Over
Energy
Curie LawCurie Law
χχMMT = ConstantT = ConstantPierre Curie, 1900 ParisPierre Curie, 1900 Paris
Curie BalanceCurie Balance
K4[Fe(II)(CN)6]
K3[Fe(III)(CN)6]
(NH4)2Fe(II)(SO4)2
Diamagnetic, spin 0
Paramagnetic, spin 1/2
Paramagnetic, spin 2
S=2S=2
S=0S=0
S=1/2S=1/2
Magnetization : how objects behave in a magnetic field ?
macro
Magnetization M(how they become « magnetized »)
Applied magnetic field H
magnet paramagnetic M = χ H, χ > 0
diamagnetic M = χ H, χ < 0
Playing with Playing with ligands, ligands, the chemist is the chemist is ableableto control to control the geometry the geometry and symmetryand symmetryof complexes of complexes ((colourcolour, , magnetismmagnetism))
Co(II)Cl2, 6H2O : from octahedral to tetrahedral
Heat
+ H2O
+ Cl-
- Cl-
quantummacro
2 Cl-
Co2+
Playing with Playing with ligands, ligands, the chemist is the chemist is ableableto control to control the the spin statespin state
Lisboa University, October 9, 2006
macro
Hysteresis allows bistability of the system
and use in display, memories …
Spin and colour changes
macro
quantumS=2S=2
[FeII(H2O)6]2+pale green
S=0S=0
FeII(o-phen)3]2+bright red
Low Low spin, chiral, spin, chiral, FeFeIIII((bipyridinebipyridine))33]]2+2+
ΛΛ ΔΔ
Playing with Playing with ligands, ligands, the chemist is the chemist is ableableto control to control the the spin statespin state
Lisboa University, October 9, 2006
Spin Cross-OverA Fe(II) « Chain » with spin cross-over
Fe
N
N N
R
N
N N
R
Fe
N
N N
R
Fe
N N
N N
N N
N N
N
N N
R
Fe
N
N N
R
Fe
N N
N N
N N
N N
Triazole substituted Ligand (R) ; insulated by counter-anionsMany groups : Leiden, Mainz, Kojima, O. Kahn, C. Jay, Y. Garcia, ICMC Bordeaux
4+
Transition Cross-over Demonstrator by Jean-François LetardThe very samples presented were synthesized by students in Paris during practical worksCourtesy Prof. C. Roux, C. Train, A. Proust
Samplecoming from
Low T
Samplecoming from High T
Spin Cross-Over Bistability Domain
The system « remembers » its thermal past !
Room Temperature
TC TC
T / K
!MT / cm3 mol
-1
250 350300
O. Kahn, C. Jay and ICMC Bordeaux
RedWhite
33
00
Discussion sur la mati Discussion sur la matière vivante,ère vivante,10ème semaine internationale de synthèse, 1938, PUF, 1943, 219-22310ème semaine internationale de synthèse, 1938, PUF, 1943, 219-223
ThenThen, , mmemory emory ??
«« It is It is an essential an essential character character of living of living being that thebeing that thesensation sensation leaves leaves traces.traces.There is nothing There is nothing comparable in comparable in material material worldworldIt is It is a real a real joke joke to to name name «« memorymemory » » the hysteresisthe hysteresisphenomenonphenomenon. » . » ……
Paul Langevin,Paul Langevin,
O. Kahn, C. Jay and ICMC Bordeaux
From the molecule to the material and to the device …
O. Kahn, Y. Garcia, Patent
May we go furtherand dream of molecular magnets
i.e. low density, biocompatible
transparentor colourful magnets ?
Do Do the chemiststhe chemistsknow howknow howto to align the align the spinsspinsof of electronselectronsin in moleculesmolecules,,parallel parallel or or antiparallel antiparallel ??
Understanding Understanding ……
why the why the spins of spins of two neighbouring electronstwo neighbouring electrons(S = 1/2) (S = 1/2) become become ::
to get magnetic compounds to get magnetic compounds ……
antiparallel antiparallel ??
S=OS=O
or or parallel parallel ??
S=1S=1
SingletSinglet TripletTriplet
if S = 0Orthogonality
>0J = 2 k + 4ßS
if S≠0;|ßS|>>kOverlap
<0
H2Aufbau
ES
ETJ
Antiferro
O2Hund
ES
ET
J
Ferro
Tell it with flowers(find the orbital) isolated
Overlap (σ) Overlap (π)
OrthogonalityFlowers from the garden
of the Gulbenkian’s FoundationLisbon
Michelangelo, Sixtin Chapel, Rome
Exchange interactions can be very weak …
order of magnitude : cm-1 or Kelvins …
≈
order of magnitude : >> 150 kJ mol-1 …
« Chemical » bonds Robust !
Exchange interactions
Energy
Please, avoidPlease, avoidpairing electronspairing electronsinto into bonds bonds ……
macro
NO2 Dimerisation
Avoid Avoid ……
... to pair ... to pair the the «« magneticmagnetic »»
électronsélectrons
Interpretation(s)
Pairing of electrons, bondingDIA-magnetic !
N
O
O N
O
O N
O
ON
O
O
Orbital
Thermodynamics (Le Chatelier …)
2 NO2N2O4Equilibrium : + Heat
Brown colorless
12
A beautiful artefact
When some residual NO is present in the vessel :
NO2 + NO N2O3Reaction :
Brown
1
2Blue green
colorless
≈ 5 Å
Cu(II) Cu(II)
Orbital Interaction …
Ligand
A B
Which ligand ? Why not …• Cyanide, CN- ?
Ligand
Museo nacional dos azulejos, Lisboa
Cyanide Ligand
Friendly ligand : small, dissymetric, forms stable complexesWarning : dangerous, in acid medium gives HCN, lethal
C≡N-
Cr(III) Ni(II)
Dinuclear µ-cyano heterometallic complexes
NB : A dissymetric ligand helps to get stable heterometallic complexes …« Birds of the same feathers flock together » …
Polynuclear complex, synthetic strategy
Hexacyanometalate “Heart”Lewis Base
Mononuclear ComplexLewis Acid
Polynuclear Complex
3-
+ 6
2+ 9+
macro
Ferromagnetic …
ErosPaul KLEE
Nocturnal separation, 1922
Ferrimagnetic …
macro
C rC u6 S = 9/2
C rNi6 S = 15/2
C rMn6 S = 27/2
Hexagonal R -3 a = b = 15,27 Å; c = 78,56 Å a = b= 90°; g = 120°; V = 4831 Å3
Hexagonal R -3 a = b = 15,27 Å; c = 41,54 Å a = b= 90°; g = 120°; V = 8392 Å3
Hexagonal R -3 a = b = 23,32 Å; c = 40,51 Å a = b= 90°; g = 120°; V = 19020 Å3
… High Spin Heptanuclear Complexes
Marvaud et al., Chemistry, 2003, 9, 1677 and 1692
electrons electrons …… WANTED ! WANTED !
How to How to manipulatemanipulateelectrons electrons betweenbetween molecules molecules ??Towards magnetsThe saga of high TC Prussian Blues Analogues
1704 …
Diesbach, draper in Berlin …
… prepares a blue pigment « Prussian blue »
… said to be the first coordination compound
2004 : 300th anniversary !
Classical Coordination Chemistry… 3[Fe(CN)6]4-aq + 4Fe3+
aq {Fe4[Fe(CN)6]3}0•15H2O
Cyanotypes
Einstein a portrait, Cyanotypes by F. Villain, CIM2, UPMC
TC ∝ z |J|
z : number of magneticneighbours|J| : coupling constantbetween nearestneighbours
TC = 5.6 K
Magnetic Properties of Prussian Blue
Néel, 1948
Ferromagnetic Prussian blue analogues …
TC ∝ z |J|
TC >> 5.6 K
JFerro > 0
Orthogonality
TC ∝ z |J|
TC >> 5.6 K
JAntiferro < 0
Overlap …
Ferrimagnetic Prussian blue analogues …
TC / K
Z
200
Ti V Cr Mn Fe Co Ni Cu Zn
300
100
• ••[Cr(CN)6]
3-
(t2g)3
d3
• ••
• •
6 F
9 AF
MnII
d5
• ••
9 AF
(t2g)3
VII
d3
• ••
• 3 F
9 AF
CrII d4
• ••
• •
• • •
6 F
NiIId8
V4[Cr(CN)6]8/3.nH2ORoom Temperature TCOn a rational basis !
Gadet et al., J.Am. Chem. Soc. 1992Mallah et al. Science 1993Ferlay et al. Nature, 1995
quantum
2[CrIII(CN)6]3-+3Vaq
2+ [V3[CrIII (CN6)]2]
0
A blue, transparent, low density magnet at room temperature
macro
DevicesBased on Room temperature Magnets
Prussian blue analogues
Permanent Magnet
Hot
CoupleSample ( MM)
Magnetic Switch… Or thermal probe …
Other device
Up to 2004 … magnetic analogues used as …
… devices and demonstratorsmacro
… another demonstrator
macro
PermanentMagnet
Sample ( MM)
Heater
… another demonstrator
macro
Single MoleculeMagnets
Chemists have managedto transform
isolated single moleculesinto magnets
=
What is named Single Molecule Magnet ?
High SpinAnisotropic
High Spin Paramagnetic Molecule
H
Single Molecule Magnet
H
Single Molecule Magnet
Towards information storage at the molecular level ?
if T < TBlocking
Single molecule magnetsz
y
x
E
- Sz
Sz
+Sz
0
DSz2
0-2-4 +2 +4
Anisotropy Barrier
Tunneling
Thermal
Activation
quantum
[Mn[Mn1212OO1212(CH(CH33COO)COO)1616(H(H22O)O)44].2CH].2CH33COOH.4HCOOH.4H2200
Mn(IV)
Mn(III)
Ion Oxyde
Carbone
S=10
or Mnor Mn1212
From D.Gatteschi and R. Sessoli
S=2
S=3/2
S =8x2 -4x3/2 =
Mn12 is a hard magnet
-3 -2 -1 0 1 2 3
-20
-10
0
10
20
T=2.1K
MA
GN
ET
IZA
TIO
N (µ
B)
MAGNETIC FIELD (T)
Bistability : inzero field themagnetisation canbe positive ornegativedepending of thestory of thesample
Coercive Field
RemnantMagnetisation
The dream …
Surface
Magnetic Tip H
≈ 10 nm
High Spin "down"
High Spin"down"
quantum macro
Surface
Magnetic Tip H
≈ 10 nm
High Spin "down"
High Spin"down"
macroquantum
… information storage at the molecular level !
Surface
Magnetic Tip H
≈ 10 nm
HSM «up»High Spin"down"
The dream …
Nanosciences …
… a challenge for chemists and friends …
Surface
H
≈ 10 nm
HSM «up»High Spin"down"
The possibilities The possibilities are are endless endless ……
as attractive but less recommended …
Another popular non scientific use
of the word « magnetism »
To To be demystified be demystified ……
An interaction An interaction through spacethrough space invisible, invisible, incomprincomprehensible ehensible ……
MagnMagneetism tism = = Magic Magic !!
Levitating top
EURASIA TRADING COMPANY 5, place Anatole France 44 000 - Nantes 45 € + 6,40 € de port
« This flask is equipped with magnets and induces in its centre an intense magneticfield which magnetizes the whole liquid.
Keep in the magnetic flask, tap or mineral water or any other drink, from 15mns toseveral hours, for an optimum magnetization.
Drink daily Magnetized Water : in preference, 1 cup when getting up, 1 or 2 in themorning and the afternoon and 1 cup at bedtime.
As a matter of fact, the body and tyhe blood are composed at 70 and 80% ofwater, hence magnetized water, more lively, more energetizing due to its magneticproperties, carries its energy into the whole organism.
Active research in hospitals, worldwide and mainly in China, havedemonstrated the beneficent effects of magnetized water.
Some specialists foresee that ..
Magnetism will play an important rôle in the world of tomorrow.
M. Noyori, Hanoi, october 2003
To daythe chemist is able
to synthesizeany molecule
at will
NEWMAGNETICOBJECTS
High spinMolcules
High TC MagnetsPhoto-Magnets
ChiralMagnets
Single Chain Magnets
BEAUTIFULOBJECTS
High spinMolcules
High TC MagnetsPhoto-Magnets
ChiralMagnets
Single Chain Magnets
NEW PROPERTIES
kId+
Id-≠
k
Unpolarised light γd(w)k.M
0
2
4
8 12 16 20 24Temperature /K
hν
0.0
0.5
1.0
1.5
2.0
3 4 5 6 7 8
!" / a. u.
T /
1000100
101
0.1
K
H
M
High spinMolcules
High TC MagnetsPhoto-Magnets
ChiralMagnets
Single Chain Magnets
Earth needs care ….
Science for peace … (Vincenzo Balzani)
Pablo PicassoChild with a dove, 1901oil on canvas, 73x54 cm
Private collectionon loan to National Gallery
Peace,PaixPace,PazPau, Friede