Solvothermal synthesis and crystal structure of Sb(III) and Sb(V) thioantimonates: [Mn(en)(3)](2)Sb2S5 and [Ni(en)(3)(Hen)]SbS4

摘要

Thioantimonate compounds of [Mn(en)(3)](2)Sb2S5 (1) and [Ni(en)(3)(Hen)]SbS4 (2) (en = ethylenediamine) were prepared by reaction of transition metal chloride with Sb and Ss powders under solvothermal conditions. Compound I consists of discrete [Sb2S5](4-) anion, which is formed by corner-sharing SbS3 trigonal pyramids. Compound 2 is composed of discrete tetrahedral [SbS4](3-) anion. The compounds 1 and 2 are charge compensated by [M(en)(3)](2+) cations, whereas in the crystal of 2 there is another counter ion of [Hen](+). The results of the synthesis suggest that the temperature, the concentration and the existing states of the starting materials and so on are important for the structure and composition of the final products. In addition, the oxidation-state of antimony might be related to the molar ratio of the reactants. Excess amount of elemental S is beneficial to the higher oxidation-state of thioantimonate (V). Compound I decomposes from 150degreesC to 350degreesC, while compound 2 decomposes from 200degreesC to 350degreesC remaining Sb2S3 and NiSbS as residues. (C) 2004 Elsevier Inc. All rights reserved.