Chemistry Reference
In-Depth Information
Fig. 9.20 Diffuse scattering intensity distribution of [Pt
2
(EtCS
2
)
4
I]
1
(2) along the
b
* axis at room
temperature [
73
]. The calculated intensities of CDW- and ACP-type structures are also plotted.
(
Inset
) Diffuse intensity distribution around (0, 5.5, 0)
Fig. 9.21 Incident X-ray energy dependence of [Pt
2
(EtCS
2
)
4
I]
1
(2) as well as the calculated
spectra for the A-type (CDW-type) structure [
73
]. (a)Pt
L
III
-edge; (b)I
K
-edge
order to determine the LT superstructure of 2, synchrotron radiation crystal structure
analysis has been performed for data taken at 48 K. When the superlattice reflections
are included,
the supercell can be indexed by
a
super
¼
0.5
a þ
0.5
b
,
b
super
¼
0.5
b þ c
, and the space group changes from
C
2/
c
to
P
¯
. Figure
9.22
shows the superstructure of 2 at 48 K [
33
]. Two crystallo-
graphic independent [Pt
2
(EtCS
2
)
4
I] units exist in a unit cell in the LT phase and the
periodicity of the crystal lattice is twofold of a -Pt-Pt-I- period. The two Pt-Pt
0.5
a þ
1.5
b
, and
c
super
¼
0.5
a
Search WWH ::
Custom Search