Theory of valence-band XPS spectra of random alloys: application to AgxPd1-x

Multiple scattering theory is used to obtain a local, one-electron approximation for calculating the valence-band XPS spectra of solids and the generalisation to random substitutional alloys is described. The nature of the final state and the influence of matrix elements on the shape of the spectra are discussed. The local approximation is shown to be rather accurate at high photon energies. The authors present calculations (based on the KKR CPA) for Ag x Pd 1-x alloys using both self-consistent and non-self-consistent potentials and compare the results with experimental data.