Some effects of intra-atomic electron correlation on XPS multiplet splittings

Large deviations between experimental and theoretical values for XPS exchange splittings have been attributed to intra-atomic correlation effects. It is shown here how these can reduce exchange splittings by a factor which is roughly independent of the valence electron configuration, spin state, or covalency. The use of splittings to measure such effects may therefore be justified, in spite of the large contributions from correlation. (orig.)