ISSN:
0009-2940
Keywords:
Bismuth subhalides
;
Band structure and electrical conductivity of Bi6Cl7
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The methods of preparation for Bi8(AlCl4)2 and Bi6Cl7 have been improved and the single crystal structures for these cluster compounds re-investigated and re-interpreted. In addition, conductivity measurements and band structure calculations using the tight-binding approximation have been performed on Bi6Cl7 and related subvalent bismuth halides. - Bi8(AlCl4)2 consists of isolated AlCl4- anions and rather undistored square-antiprismatic Bi82+ clusters with an average Bi-Bi distance of 3.10 Å. Relatively short intercluster Bi-Bi contacts of 3.90 Å suggest weak bonding interactions between the Bi82+ units. In contrast, the structure determination of Bi6Cl7 implies that this structure should be regarded as being composed of discrete Bi95+ clusters and a polymeric BiIII-Cl anionic lattice including infinite, distorted α1[Bi2Cl24+] chains. According to the experimental and theoretical results, the Bi6X7 (X = Cl, Br) family of subvalent bismuth halide compounds are anisotropic semiconductors along the crystallographic c axis. The conductivity is mediated by the onedimensional α1[Bi2Cl24+] chains. These are interconnected with the Bi95+ clusters, which are acting as electron reservoirs. The related BiX (X = Br, I) family of subvalent bismuth halides are shown to be anisotropic semiconductors in the crystallographic b direction.
Additional Material:
8 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19961291013
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