Tetrahedral d~0 and d~(10) transition metal ions sharing edges in the solid state: electronic structure and bonding

摘要

The bonding and electronic structure in one- and two-dimensional copper-vanadium sulfides, based on tight binding band calculations, has been studied. Theoretical evidence for the existence of weak donor-acceptor interactions from the d~(10) copper (I) ion toward the empty d orbitals of V~v is discussed. Maximization of the number of d~(10)-d~0 interactions explains the structural choice among alternative distributions of the transition metal ions within the sulfide matrix. The double chains of Ba_2Cu_3VS_6 and the layers of KCu_2VS_4 have an electron deficiency associated with the presence of hypervalent sulfur bridges that slightly enhances the Cu...V interaction.