Electronic structure of non-magnetic impurities in Cu

Abstract

Using density functional theory the electronic structure of 4d transition metal and sp impurities from the third, fourth and fifth rows of the periodic system in a Cu matrix is calculated self-consistently. The authors use the local spin density approximation of Hedin and Lundqvist. The impurity is embedded in the perfect crystal environment and described by a single perturbed muffin-tin potential in the KKR-Green function scheme used previously for other impurities in Cu, Ag and Al. Results are given for the local density of states, scattering phase shifts, local charges, change of density of states at the Fermi level and residual resistivity. The density of states of the virtual bound states of 4d impurities is not very Lorentzian-shaped due to a rather large d-d interaction and the local density of states at the bottom of the Cu d band is more similar to pure Cu than it was for 3d impurities. The sp impurities are electronically characterised by a piling up of s or p bonding and antibonding states at both sides of the Cu d energy region gradually shifting to lower energies when they are filled.