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

The bonding and electronic structure in one- and two-dimensional copper-van adium 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 discuss ed. Maximization of the number of d(10)-d(0) interactions explains the stru ctural choice among alternative distributions of the transition metal ions within the sulfide matrix. The double chains of Ba2Cu3VS6 and the layers of KCu2VS4 have an electron deficiency associated with the presence of hyperv alent sulfur bridges that slightly enhances the Cu ... V interaction.