X-ray-absorption spectroscopy inCoSi2andNiSi2: Experiment and theory

This paper presents an experimental and theoretical study of x-ray-absorption spectroscopy near the edge. We measured K edges for all atom types and ${\mathit{L}}_{2,3}$ edges for Co and Ni. Theoretical spectra from a linear-muffin-tin-orbitals band-structure calculation are shown. The effect of the core hole on threshold energies and absorption spectra has been studied. We also show the distribution of the photoelectron in the elementary cell. Threshold energies obtained by using the difference-self-consistent-field method are compared to experimental values. Polarization energies, due to rearrangement of the core orbitals, have been estimated for the different core holes.