o tlin outline 2007/lectures/michel 0 bangal… · 4. magnetism of molecules assemblies without...
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O tlin
ICMSICMS--ICMR Winterschool on Chemistry and Physics of Materials, Nov. 6ICMR Winterschool on Chemistry and Physics of Materials, Nov. 6--13, 2007, Bangalore13, 2007, Bangalore
1. IntroductionBrief history of molecular magnetism [1-6]
Outline
Brief history of molecular magnetism [ 6]2. Mononuclear species (complexes)2.1. Prequisites : free ion terms, states, orbitals and ligand field. Point Group Symmetry2.2. Metal-ligand interaction to tune electronic structure.2.3. Spin states, spin cross-over, devices [7]3. Magnetism of molecular assemblies in interaction. Polynuclear complexes
l h l l d l h3.1. Interaction between two electrons : phenomenological and orbital approaches3.2. Interaction Models [1]
Kahn ; comparison with Hoffmann (molecules)Comparison with Anderson, Goodenough-Kanamori (solids)
3.3. Case studies :Binuclear complexes [1 5]Binuclear complexes [1,5]Ferrimagnetic chains [1,5]Molecule-based magnets ; devices [8]
4. Magnetism of molecules assemblies without interaction :Single-molecule, single-chain magnets [9]Molecular, "bottom-up", approach of nanosystems, high spin molecules, p , pp y , g pThe "Mn12" and "Fe8" moleculesLocal anisotropy ; magnetic quantum tunneling effect.
5. ProspectsMultifunctional materials [10]Magnetism of a single molecule ; Information storage. Electronic quantum computingMagnetism of a single molecule ; Information storage. Electronic quantum computing
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molecule-based magnets ? Why ?y
L d it
Specific propertiesLow densityTransparentNanosizedOften biocompatible and biodegradableVery flexible chemistryMild chemistry : Room T Room PMild chemistry : Room T, Room P, Solution Chemistry
Fragile Agingg gDiluted
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Multifunctional materials
• Flexibility of molecular chemistryT bl St t d P tiTunable Structures and Properties
• Magnetic and optical propertiesMagnetic and optical propertiesColor, chirality, non linear optics
M ti d l t i l ti• Magnetic and electrical properties(Supra)Conducting magnetic materials
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Conducting magnets See P. Day lecture Nº2
Coronado et al. Nature 2000
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Multifunctional materials
• Interplay of Spin with Light
• Light reveals the spin (magnetisation) :
• Interplay of « Spin » with Light
Light reveals the spin (magnetisation) Photomagnetic Prussian Blues analoguesPhotomagnetic molecules
• The spin (magnetisation) transforms light :Magneto-opticsO i ll i MOptically active Magnets
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Ph t tPhotomagnets
Transforming magnetism by light
J. Miró, Muro de Luna, Mural ceramics, UNESCO, Paris
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Spin cross over
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Photoexcitation … Jablonski Diagramme
Many things can happen after excitation …
EnergySinglet Spin = 0
Intersystem crossinggy
Triplet Spin = 1hνIntersystem crossing
hν ‘
hν ‘’
Singlet Spin = 0
Coordinate
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Photomagnetism in coordination chemistry• LIESST Effect • LD-LISC Effect• LIESST Effect
Light-Induced Excited Spin State
HS
• LD LISC EffectLigand-Driven Light-Induced
Spin Change
HSHSHS HS
HSh
LShν
L
hν
D ti t l I Ch 1984 24 2174
LS
R t l I Ch 1994 33 2273
LS
hν
Decurtins et al. Inorg. Chem., 1984, 24, 2174.
NN322 nm
Roux et al. Inorg. Chem., 1994, 33, 2273.
FeII(BS) → FeII(HS)hν
T < 50 K260 nm
Trans-StpyFeII(BS)
Cis-StpyFeII(HS)T < 90 K
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« L.I.E.S.S.T. » Effect
LightInducedExcitedSpin StateStateTrapping
J.
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« L.I.E.S.S.T. » Effect , Interpretation
P. Gütlich et al. et al., Angewandte Chem., 1994
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Photoexcitation …
ESpin = 0
Many things can happen after excitation …
Energy
Spin = 1
Intersystem crossing
Metastable state(s)
Spin = 1
M ( )
• LIESST EffectLi h I d d E i d S i SSpin 1
Spin = 0
Light-Induced Excited Spin State
• LD-LISC Effect
CoordinateLigand-Driven Light-Induced Spin Change
S.Decurtins, A. Hauser, P. Gutlich Inorg. Chem. 1984, 24, 2174C. Roux, J. Zarembovitch et al. Inorg. Chem. 1994, 33, 2273
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Gymkhana campus Bangalore, December 8, 2007
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1) Ph t ti1) Photomagnetism= Transforming magnetism by light
2) Magneto optics2) Magneto-optics= Transforming light by magnetism
3) Applications3) Applications= Writing and reading
magnetic information with lightmagnetic information with light
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What about the 8 branches star?What about the 8 branches star?Octacyano Complex ?
PolynuclearComplexp
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Interaction with lightOctacyanometalate Precursors Heptanuclear Complexes
WIVC II WIVNiII WIVM IIWIVCuII6
MoIVCuII6
WIVNiII6MoIVNiII6
Monoclinic P na = 24 89 Å; b = 14 39 Å; c = 30 11 Å
Monoclinic 22 03 Å b 28 39 Å 22 01 Å
Monoclinic C ca = 25 39 Å; b = 15 22 Å; c = 30 72 Å
WIVMnII6
MoIVMnII6
a = 24.89 Å; b = 14,39 Å; c = 30,11 Åa = g = 90°; b = 108.81°;
a = 22.03 Å; b = 28,39 Å; c = 22,01 Åa = g = 90°; b =99.48°;
a = 25.39 Å; b = 15,22 Å; c = 30,72 Åa = g = 90°; b = 111.45°;
V. Marvaud, J.M. Herrera, work in progress
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MoCu6 : Photomagnetic high spin molecule
hν (=405 nm), 19 h 5 K 5,0
6 x S = 1/2
S = 364 % S = 3
After hν
After hv and T> 300 K
Before hν4,0
4,5
mol
-1.K
)
h
3,0
3,5
χT (c
m3 .m hν406 nm
0 50 100 150 200 250 300
2,5H = 20000 G
T (K)
Collaboration: C. Mathonière, ICMC Bordeaux
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Photo-induced electron transferPhoto-induced electron transfer
MoIV CuIIhν MoV CuI
5
MoIVCuII MoVCuI CuII
+5 +5
Mo VCu 6 MoVCu 1Cu 5MoV, d1 , S=1/2
Ferro interaction …MoIV, d2 , S=0No exchangeNo exchange6 isolated S=1/2 S=3
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10
12
MoCu6BT avant Ir
Evolution de MoCu6 avant Ir, apres Ir et apres relaxation
8
10 MoCu6BT, avant Ir
MoCu6BTI2, apres Ir
RT Apres relaxation
4
6
Abs
orba
nce
2
4
0
2510 2520 2530 2540 2550 2560
EnergieEnergie
From V. Marvaud, F, Villain, A. Bachschmidt, Elettra, Triesta
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MoCu6 : Magnetization under Irradiation in a microSQUID
4
60.008 T/s
2
4
B
0
M/N
µ B
-4
-2 0.04 K0.5 K1 K2 K
0.04 K0.5 K1 K2 K
0 h 10 h
-6-1 -0 5 0 0 5 1
2 K4 K
2 K4 K
1 0.5 0 0.5 1µ0 H (T)
V. Marvaud and Wernsdorfer, Louis Néel Laboratory, Grenoble
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Looking at ther Mo-Cu compounds (also W analogues)
Monoclinic P 21/ca = 10.514 Å; b = 14.584 Å; c = 22.182 Åα = γ = 90°; β = 96 18°; V= 3381 4 Å3
MoIVCu2-(tren)
Monoclinic P 21/aa = 14.790 Å; b = 15.901 Å; c = �18.395 Å
MoVCu (AF, S=0)
α = γ = 90 ; β = 96.18 ; V= 3381.4 Å3
MoVCu4
α = γ = 90°; β = 109.208°; V= 4085.2 Å3
Orthorhombic P bcma = 10.388 Å; b =22.000 Å; c = �30.172 Å
α = β = γ = 90°; V= 6895.4 Å3
NH2
N NH2
H2N
MoIVCu6-(TPA)
Monoclinica = 27.0�95 Å; b = 17.13�5 Å; c = 33.172 Å
α = γ = 90°; β = 66.42°; V= 14114 Å3
NH2 H2N
li i 21/
N
N N
N
MoIVCu6
Monoclinic P na = 24.89 Å; b = 14,39 Å; c = 30,11 Å
α = γ = 90°; β = 108.81°;
Monoclinic P 21/na = 14.292 Å; b = 24,554 Å; c = 15,017 Åα = γ = 90°; β = 108.78°; V=4989.6 Å3MoIVCu6-Cis
TPA
Work by V. Marvaud et al.
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Theoretical Study (DFT)Theoretical Study (DFT)
Collaboration : J.Tercero, E. Ruiz, S. AlvarezBarcelona University
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Molecular Orbitals [Mo(V)(CN) ]3- (DFT)[Mo(V)(CN)8]3 (DFT)
Mo Square Antiprism Mo DodecahedronMo Square Antiprismd z2
Mo Dodecahedrond x2 -y 2
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Molecular Orbitals for a pair[Mo(V)(CN) ] CN Cu(II)[Mo(V)(CN)7]-CN-Cu(II)
Dinuclear MoCu square antiprism Dinuclear MoCu dodecahedron
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3,00000
SAP CSM - (Photo)MagnetismAntiprism
2,50000 WIVCu2SAPR
Antiprism
2,000001MoIVCu6FM
MoVCuAF
1'WVCuAFMoIVCu6FM(Trifl)
1'MoIVCu6FM
WIVCu4FM
1WVCuAF
1,50000Est1
2MoIVCu6FM
CuWV5 FMMoVCuFM(cyc)
MoIVCu2(en)N3D
1 Mo Cu6FM
2'MoIVCu6FM
Photomagnetism
0 50000
1,00000
Est2 MoIVCu6(Tpa) Dodecahedron
0,00000
0,50000
Est3DD
MoIVCu2
MoIVCu2(cyc)N2D
MoIVCuAF(bipy)
Dodecahedron
,0,00000 0,50000 1,00000 1,50000 2,00000 2,50000 3,00000 DD
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in Prussian blue analogues … (3D) g ( )
Photomagnetism
C III F II [(C II(HS)F III(BS)]*hν
CoIII-FeII ⇒ [(CoII(HS)FeIII(BS)]*diamagnetic pairs paramagnetic
3D ferrimagneticbelow TCbelow TC
Hashimoto et al., Science, 1996 ; Verdaguer, Science, 1996
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Photomagnets Cobalt-Iron Prussian blue analogues
The properties are deeply modified by the insertion of alkali cations
Co4[FeIII(CN)6]8/3•nH2O Cs2CoIII10/3CoII
2/3[FeII(CN)6]10/3 Cs4CoIII4[FeII(CN)6
8
on /
10-3
em
u
No effect of light
on /1
0-3
emu
neti
zati
on 1
0-4 /e
mu
4
4
2.5
Very small effect of light
n /1
0-3
emu4
h
0
4
5 10 15 20 25
Mag
neti
zatio
Mag
netiz
atio
Temperature /K
Mag
n
248 12 16 20
0
2
8 12 16 20 24
1
Temperatu re /K
Mag
netiz
atio
n
0
2
8 12 16 20 24T t /K
hν
Temperature /K Temperature /KTemperature /K
Under pressure V. Ksenofontov P. Gütlich, A. Bleuzen et al. Phys. Rev. B, 2003, 68, 0244151-6A. Bleuzen et al. Angew. Chem. Int. Ed., 2004, 43, 3728.
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Synthesis.[FeIII(CN)6]3- + [CoII(H2O)6]2+ + C+ (C+=K+, Rb+, Cs+)
increasing size of the cation C
Rb1.8Co4[Fe(CN)6]3.30 13H2O Cs3.7Co4[Fe(CN)6]3.7 9.2H2OK0.1Co4[Fe(CN)6]2.8 18.4H2O
increasing size of the cation C
K+ Rb+ Cs+
O
O
O
O
OO
O
O
Fe/Co 0.70 0.83 0.93
IIIN C-N
C-N O
O
O
O
O
O
O
O
N
Co ligand field
CoIII -FeII
rally induced CoIIN4O2
CoIIIN6
a = 10.04 ± 0.05 Å
a 10 36 ± 0 05 Å
Co
N
N N
NN
N
Co
N
N O
O
CoII-FeIIIstructurally ind
electron transfera = 10.36 ± 0.05 Å
∆ 0 3 ÅN
N
O ∆a = 0.3 Å
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Formation of CoIII-FeII pairs …I ti f lk li tiInsertion of alkali cation …
1) + n C+
Fe(CN)6
2) + n/3 [Fe(CN)6]3-
O
OO
O
OO
OO
O
OO
O
Fe(CN)6Co
H2OC N
OO
O
O
O
O
Co(NC)4+n/2(OH2)2-n/2
C-N O
• Insertion of C+ increases the ligand field ∆Co of Co(II)g Co ( )
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Cobalt(II) : Ligand Field, spin state, geometry and reactivity
H O OHOH2
NC CNCN
CN NCNC
H2OCo
H2O OH2
OH2OH2
NCCo
NC CN
CNCN
CNCo
CN NC
OH2OH2OH2 CN
E² ² t
OH2
²² oct oct² oct
Strong FieldIntermediate FieldWeak Field Strong FieldLow SpinS = 1/2
Very Reducing Short Co-C
Intermediate Field Spin Transition ?
S = 3/2 or 1/2Reducing
Weak FieldHigh SpinS = 3/2Long Co-O Very Reducing Short Co CReducingLong Co O
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CN
Origin of the diamagnetic pairs in Co-Fe Prussian Blues
NC FeIIINC CN
CN
CN
C NC FeIINC CN
CN
CNCoII
CN N
OH2
CNCN
C
CNCoIII
CN N
OH
NC FeII
CNCN
C215 pm
195 pm2
OH2
CN OH2OH2
E eg*e * El fAntibonding ! g
t2gt2g
eg* Electron transferAntibonding !
2g2g
HS CoII LS FeIII LS CoIII LS FeII
Paramagnetic : 3/2, 1/2 Diamagnetic : 0, 0Paramagnetic 3/2, 1/2 Diamagnetic 0, 0Distance CoIINeighbours 215 pm Distance CoIINeighbours 195 pm
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Photo-induced electron transfer L l t t d C
• Photo-induced electron transfer = important dilation of the network
Local structure around Co.p
Rb1.8Co4[Fe(CN)6]3.30 Cs3.7Co4[Fe(CN)6]3.7hν =
defects = strains relaxation easy dilation
dilation strong strains very small effect of light
Rb C• Excited pairs CoII-NC-FeIII - same electronic structure - same local structure
Rb2 Cs4
as CoII-NC-FeIII pairs in K0.1Co4[Fe(CN)6]2.8
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Oxidation StateOxidation StateXANES at the Co K edge : 1s2 4p 1s1 4p1
[CoII(OH2)6]2+
orba
nce
/a.u
.
1
23
K+
Rb+
Cs+
CoII
CoIII ]
Abs
o
[CoIII(CN)6]3-
Cs
• K0.1CoII4[FeIII(CN)6]2.8 18.4H2O
7700 7720 7740 7760 7780 7800Energy /eV
• Rb1.8CoII0.7CoIII
3.30[FeII(CN)6]3.30 13H2O • Cs3.9CoIII
4[FeII(CN)6]3.9 9.2H2O
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Photoinduced electron transfer …hν
Spin = 0Intersystem crossing
[Co(II)-Fe(III)]*Co(III)-Fe(II)hν
Spin = 1
Energy Intersystem crossing+ Electron transfer
Spin = 1 Metastable stateSpin 1
Spin = 0 Co Fe distance
Metastable state
Pair : Paramagnetic3D : FerrimagneticCo-Fe distance 3D : Ferrimagnetic
Co(III)-Fe(II)
Diamagnetic
[Co(II)-Fe(III)]*
ParamagneticDiamagnetic Paramagnetic
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Towards devices … ?
Magneto-opticsg pHow magnetism transforms light …g g
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1
Eff
et
0
0,005
0,01
0,015
2 he res
Faible flux lumineuxP = 0.7 mW /mm2Spot du�
laserMagneto-optics
Le composˇ est initialement faiblement paramagnˇ tique�Le syst me ne transite pas sous faible flux lumineux
Champ /Oe
-0,015
-0,01
-0,005
-8000 -6000 -4000-2000 0 2000 4000 6000 8000
2 heures
Echantillon Reading
Le syst¸ me ne transite pas sous faible flux lumineux
0,005
0,01
0,015
Fort flux lumineux0 / 2S t d �
2 Writing
-4000 -3000- 2000 -1000 0 1000 2000 3000 4000
Champ /Oe
Eff
et
-0,015
-0,01
-0,005
0
2 heuresP = 70 mW /mm2
Au même point de
l'échantillon
Spot du�laser
Echantillon
Example of a+ Reading
Le syst¸ me transite sous fort flux lumineux = ECRITURE
0,0153
Example of aphotomagneticerasable
d it blAu même point de
l'échantillon
Spot du�laser
Echantillon
Eff
et
-0,015
-0,01
-0,005
0
0,005
0,01Faible flux lumineux
2 heuresP = 0.7 mW /mm2
3and rewritablememory
ReadingEchantillon
Champ /Oe-4000 -3000- 2000 -1000 0 1000 2000 3000 4000
Le signal dichro•que est tr¸ s faible : une partie des paires excitˇes relaxent
LECTURE
Coll. J. Ferré, J.P. Jamet, LPS Orsay
g
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Next step : going to nanosize
200 200 nm200 nm
x 23000 nanometricr anisati n
200 nm
nanoparticles organisationof particles
A. Bleuzen, LCI Orsay, private communication
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Work in progress : Magnetization of a few nanoparticles of CoFe Prussian Blue analogues, microSQUID, 4 K, under irradiaction
14 K
g , Q , ,
0.5
4 K
A50
00 min
M/M
s
irradiation with white light
-0.5
0 min1 min5 min20 min30 min70 min100 min3 h
-1-1 -0.5 0 0.5 1
3 h4 h12 h
µ0 H (T)µ0 ( )
(A. Bleuzen, W. Werndorfer)
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Chi l M tChiral Magnets
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Optically Active Magnets : Why ?
θθn
εn-θn
M
M
θm
εm-θm
-εnCotton Effect Faraday Effect
M-εm
Cotton : breaking of space symmetryFaraday : breaking of time symmetry
Formal Similarity of Faraday and Cotton Effects
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MichaelMichaelMichaelMichaelFaradayFaraday ……FaradayFaraday ……1791-1867Fullerian Professor of Chemistry1833-1867
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andand…… and and AiméAiméAiméAimé
CottonCotton
1869 - 1951French PhysicistOptical Physics
Circular dichroïsmCircular dichroïsm
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What is new with Optically Active Magnets ?
Breaking of space and time symmetry
Cross-effect MagnetoCHiral Dichroism (MChD)
Unpolarised light
k Id+
≠
contributionγd(ω)k.M
to theUnpolarised light
k Id-
≠
dielectric tensor
L.D. Barron, J. Vrbancich, Mol. Phys. 51 (1984) 715
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Magnetochiral Dichroism (MChD) :
µ(k,M,ω) = αd,l(ω)k + β(ω)M + γd,l(ω)k.M
CottonChi lit
FaradayM ti ti
Cross-Term2 d dChirality Magnetisation 2nd order(MChD)
k light wave vectorM magnetisation
Cf Barron, Rikken ...
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Oxalate ligand1. Bis-Chelating
2 Stable (and inert) precursors complexes2. Stable (and inert) precursors complexes
3. Complexes as ligands
O
O
M'O
O
OM
O O
O
OO
O
O
M'O
MO O
O
OO
O
O
O
O
O
1 O OO
O
OO
M' 3
OO
O 21
Chiral complex
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STRUCTURES OF 2D and 3D NETWORKS
Λ∆
ΛOO
MM1
L. Atovmyan et al, JETP Lett. 1993, 58, 766
2D∆∆
ΛOO
M2M1
∆ − Λ
Heterochiral Honeycomb Plane 2D Materials∆-Λ
Heterochiral Honeycomb Plane 2D Materials
ΛΛΛ
Λ ΛΛ
S. Decurtins et al, Inorg. Chem.1993, 32, 1888
3DO
O
O
O
M2M1
Λ − Λ or ∆ − ∆
Λ ΛΛ
ΛΛ 3D
Λ-Λ ou ∆-∆Λ Λ or ∆ ∆Homochiral Helix Structure 3D Materials
Interconnected helices
Λ-Λ ou ∆-∆
Fabrice Pointillart, Ph.D ThesisFabrice Pointillart, Ph.D Thesis
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A very useful cation for chiral design
∆-[RuII(bpy)2(ppy)]+
• dimension• D3 Symmetry• Charge : +1g
ll lé
Cf Clément et al., Monatsh. Chem. 497 (2002), 117
Gruselle, Malézieux, Brissard …
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BUILDING the 3D NETWORKS. Decurtins et al, Inorg. Chem. 1993, 32, 1888 R. Andrès et al, Inorg. Chem. 1999, 38, 4637 , g , ,
R. Andrès et al. Inorg. Chem. 2001, 40, 4633
The anionic subnetwork WRAPS around the assembling cation [Ru(bpy)3]2+
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Helix PHelix M
STRUCTURES of 3D NETWORKSeHelix M
(P)(M)
Anionic Subnetwork Cationic Subnetwork[M(L)3]n+
- Cation Symmetry D3
Charge and
[MaMb(ox)3]n-
- Charge and size ad hoc
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INDUCING CHIRALITY
Ru – N : 2,063(5) Å
{[RuΛ(bpy)3][Mn2Λ(ox)3]}n
Groupe d’espace : P4132
Mn – O1 : 2,135(5) Å
Mn – O2 : 2,169(5) Å
a = 15,508(1) Å
α = β = γ = 90°
{[Ru∆(bpy)3][Mn2∆(ox)3]}n
Groupe d’espace : P4332
a = 15,492(2) Å
Ru – N : 2,059(4) Å
Mn – O1 : 2,167(5) Å
α = β = γ = 90° Mn – O2 : 2,133(5) Å
The assembling chiral cation [Ru(bpy)3]2+ induces chirality on all the metallic centres of the anionic subnetwork
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[Ru(bpy)2 (ppy)][MnCr(ox)3][ ( py)2 (ppy)][ ( )3]
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They are chiralThrough resolved precursor [∆ or Λ MIII(ox)3]3-
NBu4[MnΛCr∆(ox)3]NBu4[MnΛCr∆(ox)3]
300
350
100
150
200
250
ΛCottonEffect
-100
-50
0
50
300 350 400 450 500 550 600 650 700
Effect
300
-250
-200
-150
-100
∆
-350
-300
Wavelength / nm
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2D or 3D : Magnets below 10-20Kg
2 5
3.0
3.5
50
60
70
cm-3
1 5
2.0
2.52D-{MnCr}
20
30
40
M /
µ B
χ−1 /
mol
.c[Ru(bpy)3][ClO4][MnCr(ox)3][R (b ) ( )][M C ( ) ]
0 5
1.0
1.5
0 50 100 150 200 250 3000
10
T / K
M [Ru(bpy)2(ppy)][MnCr(ox)3][Ru(bpy)2(ppy)][NiCr(ox)3]
0 2 4 6 8 10 12 14 16 18 20
0.0
0.52D-{NiCr}
T / K0 2 4 6 8 10 12 14 16 18 20
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TBAC NiO T 4 4K (l 580 )
Evidence of the MChD unpublished …3000 250
TBACrNiOx T= 4.4K (l=580 nm)
Phase Delta / °
Phase Lambda / ° ∆
2000
2500
200M Delta / ua
M Lambda / ua
Phase Lambda / °
Phase°a gr
ee
∆
1500150
sign
al d
elta
/ua P
hase delta
≈ 180°
nal /
ua
se /
deg
500
1000100M
s/ °
Sign
Pha
Λ
00
0
0
50
-500 0-100 0 100 200 300 400 500 600 700
H / mVC. Train, Coll. G. RikkenDFG MM SPP
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Noyori museum, nagoya
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On the way to transparent single crystals(work in progress)(work in progress)
R. Gheorghe, M. Gruselle, C. Train
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1. (NH4)3[Cr(C2O4)3] + Mn(NO3)2+ ... 2. (NH4)3[Cr(C2O4)3] + Mn(NO3)2+ …
HCH3
CH3
+
H CH3CH3
+S+ R-N+ CH3
CH3
CH3
I- N+
CH3
CH3
CH3
I-S+ R-
NMePr2(S+)-secBuI NMePr2(R-)-secBuI
[NMePr2(S+)-secBu]3[Mn-∆-Cr(C2O4)3] [NMePr2(R-)-secBu]3[Mn-Λ-Cr(C2O4)3]
R. Gheorghe, M. Gruselle, C. Train
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Structure of one of the enantiomers
Along a axis
Pl bHexagonalP 63 (no 173)Plane ab P 63 (no. 173)a = 9.4160 Åc = 16.8430 ÅVolume = 1293.11 Å3
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