DFT-calculations of polymeric systems containing d-metals

Results of a theoretical study of the electronic properties of polymeric systems [M(C2X4)]n, with M= Ni, Cu, Zn and X= O, S, Se, are presented. The calculations were carried through using a first-principles density-functional method (DFT-LMTO full-potential). We analyze the effects of varying the torsion angle between adjacent unit cells including its influence on the metal-ligand orbital overlap. The frontier orbitals depend strongly on the ligand, and the conductivity of the systems is predicted to be very dependent on the oxidation state of the metal (i.e., also on the presence of counterions). The Fermi level depends on X as well as on M.