Transcript スライド 1

May 16, 2012 for Shoshin Study Tour 2012
- Study Association Arago (the University of Twente, Netherlands)
Division of Molecular Materials Science
Research Center for Low Temperature and Materials Sciences, Kyoto University
Synthesis of Functional
Materials
Structural Analysis &
Physical Properties
examination
Design of New Materials
http://mms.ltm.kyoto-u.ac.jp/index_e.html
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History of Molecular Conductors
1954 Organic Semiconductor
• Br2
Increment of Dimensionality
1980s: Organic Superconductors
H3C
Se
Se
CH3
H3C
Se
Se
CH3
Q1D Superconductors
max. Tc = 1.4 K (AP)
1960s 1D Organic Metals
S
S
NC
CN
S
S
NC
CN
Molecular Degree of
Freedom
Lattice point
 Simply a point
 Size
 Shape
 Functionality
S
S
S
S
S
S
S
S
2D Superconductors
max. Tc = 12.3 K (AP)
1990s: 3D Molecular Superconductors
max. Tc = 33 K (AP)
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Charge-Transfer Complex Formation  Molecular Conductors
for example
Electro-oxidation
To endow the electrical
conductivity to molecular
based materials, the chargetransfer complex is formed
by treated with donor/
acceptor molecules or by
electrochemical method.
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(EDO-TTF)2PF6 — Above and Below TMI (280 K)
Distinct Molecular Deformation
Overlap
Integral
from
PF6
Bond
Rotation Length
Uniform
Isotropic
0.5+
Alternate
Uniaxial
1+/0
Peierls
OrderDisorder
Charge
Ordering
Molecular Deformation is regarded as the
Origin to Mix Metal-Insulator Transition
Mechanisms (Multi-instability).
(Overlap Integral  103)
A. Ota et al., J. Mater. Chem., 12(9), 2600-2602 (2002)
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Photo-Induced Phase Transition (PIPT) of (EDO-TTF)2PF6
Thermal Transition
PIPT
1.70 eV
1.55 eV
1.38 eV
Time Delay
Sample
Probe (white light)
Pump (1.55 eV= 12.5  103 cm-1)
Responce < 0.1 ps
Relaxation to meta-stable
state ≈ 1.5 ps
Probe 1.38 eV
(11.1  103 cm-1)
1.70 eV
1.38 eV
1.55 eV
Probe 1.70 eV
(13.7  103 cm-1)
1 photon / 50-500 molecules
Ultra-fast & Highly Efficient PIPT Material
M. Chollet et al., Science, 307, 86-89 (2005) [Erratum: 312, 697 (2006)]
H. Yamochi, S. Koshihara, Sci. Technol. Adv. Mater., 10(2), 024305/1-6 (2009)
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PI Process over 100 ps
Three-level Rate Equation
100 ps order
B: Thermally Induced Metal
10 ps order
C: Charge Randomization
+ Photo Induced Carrier
+ .....
0.1 - 1 ps
Insulator
Low Temp. Phase
A: (1010) phase
Fluctuated Charge Order
<Recent Result>
PIPT Route is
Analyzed.
N. Fukazawa et al., J. Phys. Chem. C, 116(9), 5892-5899 (2012)
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Recent Publications
▪ ▪ ▪ ▪ ▪ many corroborations with other laboratories
& the derivatives
213.
212.
209.
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199.
T. Hiramatsu et al., Physica Status Solidi C, 9(5), 1155-1157 (2012)
M. Ishikawa et al., Physica Status Solidi C, 9(5), 1143-1145 (2012
N. Fukazawa et al., J. Phys. Chem. C, 116(9), 5892-5899 (2012)
K. Onda et al., Physica B, 405(11), S350-S352 (2010)
X.F. Shao et al., Physica B, 405(11), S75-S78 (2010)
T. Murata et al., Physica B, 405(11), S45-S48 (2010)
(C60) Materials
208. D.V. Konarev et al., Inorg. Chem., 51(6), 3420–3426 (2012)
207. D.V. Konarev et al., New J. Chem., 35(9), 1829-1835 (2011)
197. D.V. Konarev et al., Inorg. Chem., 49(8), 3881–3887 (2010)
Other Materials
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H. Yamochi et al., Physica Status Solidi B, 249(5), 1012-1016 (2012)
T Ishikawa et al., J. Phys.: Condens. Matter, 24(19), 195501/1-9 (2012)
T. Haneda et al., J. Mater. Chem., 21(5), 1621-1626 (2011)
G. Saito et al., Bull. Chem. Soc. Jpn., 83(12), 1462–1480 (2010)
Y. Nakano et al., Physica B, 405(11), S198-S201 (2010)
T. Shirahata et al., Physica B, 405(11), S61-S64 (2010)
Y. Nakano et al., Physica B, 405(11), S49-S54 (2010)
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