The electronic spectra and magnetic behaviour of some dithiocacodylate complexes

Abstract

The large nephelauxetic effect and low ligand field strength produced by the dithiocacodylate group [(CH₃)₂AsS₂-] in complexes with Ni²⁺, Co²⁺, and Cr³⁺ is explained in terms of significant covalency of the metal- sulphur bonds. The Mn²⁺ compound, however, has properties consistent with considerable ionic character.     The electronic spectrum and magnetic behaviour of bisdithiocacodylato-cobalt(II) can be better interpreted in terms of tetrahedral rather than octahedral CoSx microsymmetry. On the other hand, the Ni²⁺ compound is square-planar and both the Mn²⁺ and Cr³⁺ compounds appear to be octahedrally coordinated by sulphur atoms.