Exchange, spin-orbit, and correlation effects in the soft-x-ray magnetic-circular-dichroism spectrum of nickel

Abstract
A tight-binding analysis of soft-x-ray-absorption and magnetic-circular-dichroism (MCD) spectra on Ni at the 2p→3d thresholds yields values for the valence spin-orbit parameter and exchange splitting which are, respectively, larger and smaller than the ground-state band-structure values by a factor of ∼2. The discrepancies are attributed to core-hole correlation effects. A feature that appears 4 eV above the main white lines, but only in the MCD spectrum, is also attributed to correlation effects.