X-ray Rietveld
structure refinement and bond-valence analysis of Cs2TeI6
Chem.
Met. Alloys 3
(2010) 108-114
https://doi.org/10.30970/cma3.0127
V.I. SIDEY, O.V. ZUBAKA, I.P. STERCHO,
E.Yu. PERESH
The crystal structure of the ternary iodide Cs2TeI6
has been refined by Rietveld analysis of X‑ray
powder diffraction data. The refinement
procedure was stopped when the intensity residual RB =
3.7 % had been reached. Cs2TeI6 crystallizes
in the cubic K2PtCl6 structure type, space group Fm-3m
(No. 225), with the lattice parameter a = 11.6939(8) Å, Z =
4, Dc =
4.797(1) g/cm3. The reliability of the structural model
obtained for Cs2TeI6 in the Rietveld
refinement was confirmed by a bond-valence analysis of the structure. For the
first time, the bond-valence parameters (r0 =
2.782 Å and b = 0.37 Å) have been
determined for the Te4+/I– ion pair, from a set of 14
well-determined coordination shells [TeIn].
These parameters show a reasonably high performance and can be recommended for
routine bond-valence analyses of structures containing Te4+–I–
chemical bonds.
Crystal structure of K2PtCl6:
[PtCl6] coordination octahedra and K
atoms.
Keywords
Ternary halides / Crystal structure /
Bond-valence model