Single-crystal structure of the Cs2Re6S6Br8 rhenium thio-bromide with acentric Re6 octahedral cluster units
Pilet G., Cordier S., Perrin C., Perrin A.
Ключевые слова: rhenium, octahedral cluster, structure, disorder
Страницы: 731-739
Подраздел: СТРУКТУРА ЖИДКОСТЕЙ И РАСТВОРОВ
Аннотация
Cs2Re6S6Br8 (trigonal, a = 10.001(5) Å , c = 14.676(5) Å ) exhibits the same structure as Cs2Mo6Cl8Br6 and Cs2Mo6Br14 that were described in a non-centro- and centrosymmetric space groups, respectively. The structure has been refined in P31c space group from a single crystal of actual composition Cs1.95(1)Re6S5.82(3)Br8.19(3) close to the cesium-rich end of the solid solution Cs2Re6S6Br8 — CsRe6S5Br9. The centrosymmetry is respected by almost all the atoms of the asymmetric unit, but it is clearly broken by significant differences in the S/Br statistical distribution of the disordered ? inner? ligands around the Re6 cluster. Structural refinements from data collected at 100 K revealed that the Cs cation disorder is static. From the structure refinements, the stable isomers of the [Re6S6Br2] and [Re6S5Br3] cluster cores have been unambiguously determined.
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