Complete Solution of the Korringa-Kohn-Rostoker Coherent-Potential-Approximation Equations: Cu-Ni Alloys

Abstract

We report on calculations of the electronic states in disordered ${\mathrm{Cu}}_{c}{\mathrm{Ni}}_{(1\ensuremath{-}c)}$ alloys based on a complete solution of the coherent-potential approximation for a muffin-tin model of the alloy potential [Korringa-Kohn-Rostoker coherent-potential-approximation (KKR-CPA)]. The computational effort required is modest on the scale of that involved in bandstructure calculations for many atoms per unit cell. The calculated densities of states are in good agreement with the results of photoemission and other experiments. The adequacy of previous approximate KKR-CPA and averaged $t$-matrix calculations is discussed.