Theoretical study of the electronic structure of ordered and disorderedCu3Au

Abstract

The electronic structure of the ordered phase of ${\mathrm{Cu}}_3$Au is investigated using the self-consistent-field (SCF) fully relativistic linear-muffin-tin-orbital method. The electronic structure of the disordered phase is obtained from a fully relativistic Korringa-Kohn-Rostoker coherent-potential-approximation calculation. To show the effects of self-consistency in the disordered phase, we present both non-SCF and SCF results for this phase. These results show that the largest changes in the electronic structure upon ordering are in energy regions away from the Fermi energy. To verify this prediction we have calculated the x-ray-photoemission (XPS) intensities for both phases and compared these to experimental data. It is found that the calculated Al Kα XPS intensity is in excellent agreement with the data on the ordered system and gives a clear picture of the itinerant nature of the Au 5d states. For the disordered state our results are in agreement with trends seen in angle-resolved photoemission, but are in disagreement with the only angle-integrated XPS data available on the disordered system.