Chemistry Reference
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Table 10.3 Photon energy of
the peak in optical
conductivity spectra of the
present MMX chains. Photon
energy attributed to strong
lowest charge transfer (CT)
band are indicated by
boldface
Complex
Photon energy/eV
K
2
(NC
3
N)[Pt
2
(pop)
4
I]
4H
2
O
0.85, 2.15, 3.25, 3.95
K
2
(Me-NC
3
N)[Pt
2
(pop)
4
I]
4H
2
O
0.85, 2.23, 3.30, 3.83
K
2
(Cl-NC
3
N)[Pt
2
(pop)
4
I]
4H
2
O
0.89, 2.28, 3.26, 3.9
K
2
(
cis
-NC
4
N)[Pt
2
(pop)
4
I]
4H
2
O
0.79, 2.22, 3.18, 3.91
K
2
(
trans
-NC
4
N)[Pt
2
(pop)
4
I]
4H
2
O
0.81, 2.22, 3.19, 3.92
K
2
(NC
5
N)[Pt
2
(pop)
4
I]
4H
2
O
0.64, 2.19, 3.18, 3.94
Rb
2
(NC
3
N)[Pt
2
(pop)
4
I]
4H
2
O
1.14, 2.13, 3.29, 3.86
Rb
2
(Me-NC
3
N)[Pt
2
(pop)
4
I]
4H
2
O
1.14, 2.2, 3.29, 3.80
Rb
2
(Cl-NC
3
N)[Pt
2
(pop)
4
I]
4H
2
O
1.12, 2.2, 3.27, 3.78
Rb
2
(
trans
-NC
4
N)[Pt
2
(pop)
4
I]
2H
2
O
0.94, 2.16, 3.18, 3.80
Rb
2
(NC
2
OC
2
N)[Pt
2
(pop)
4
I]
4H
2
O
0.92, 2.15, 3.19, 3.82
Fig. 10.6 Phase diagram in
already-known pop-type
MMX chains (
black
) with the
plot of MMX chains with
binary countercations (
red
triangle
for CDW state;
green
square
for ACP + CDW
state).
Solid line
is the fitting
of the data of already-known
pop-type MMX chains with
unitary countercation in each
phase
CP
CDW
2
MMX chains with
unitary countercation
binary countercations in
CDW state
ACP+CDW state
1
0
6
6.5
7
d
(Pt-I-Pt) / Å
d
(Pt-I-Pt) is applied in the case of ACP + CDW state, on the assumption that the
effect of
d
(Pt-I-Pt) on the perturbation to energy level of Pt ions is averaged. All
MMX chains with binary countercations obey the fitting line in CDW state,
indicating that the charge transfer occurs from electron-rich Pt dimer to electron-
poor Pt dimer in ACP + CDW state as well as in CDW state. The peak energy of the
weak bands were almost independent of the compounds and nearly identical to that
of MMX chains in typical CDW state [
51
,
52
], which also support that the
electronic structure in ACP + CDW state is similar to that in CDW state. These
results are consistent with the nonmagnetic property of K
2
(NC
3
N)[Pt
2
(pop)
4
I]
4H
2
O[
46
,
53
].
Consequently, the introduction of the ACP-like distortion into MMX chains can
be controlled by changing the length of B
2+
, with retention of the electronic
structure of CDW state.
10.2.5 Structural Features of MMX Chains with Binary
Countercations
Compared with MMX chains with unitary countercation, those with binary
countercations have two important structural features. One is the “synchronized” packing.
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