Calculation of self-consistent potentials for substitutionally disordered systems with application to theAgx−Pd1−xalloy series

Abstract

Previous Korringa-Kohn-Rostoker coherent-potential-approximation electronic-structure calculations for substitutionally random alloys have been based on ad hoc potentials. The lack of procedures suitable to provide self-consistent, parameter-free potentials prevented computations for systems consisting of dissimilar atoms and is also the reason why quantities like, for example, cohesive energies or lattice constants, have not so far been evaluated for systems of similar constituents. We present in full detail a generally applicable scheme devised for calculating the self-consistent electronic structures of substitutionally disordered systems. Its feasibility is demonstrated by presenting the results obtained for the ${\mathrm{Ag}}_x{\mathrm{Pd}}_{1-x}$ alloy series. They are compared with those of former non-self-consistent calculations which use Mattheiss prescription potentials and the $\alpha =1\mathrm{}$ Slater exchange, whereas the von Barth—Hedin expression is employed in our work. The differences are perceptible and have to be understood as combined self-consistency and exchange-correlation effects.