LIFETIME EFFECT ON THE MULTIPLET STRUCTURE OF 4D X-RAY-PHOTOEMISSION SPECTRA IN HEAVY RARE-EARTH ELEMENTS

X-ray-photoemission spectra of 4d(N4,5) core level in heavy rare-earth elements are studied theoretically with the consideration of the 4d-4f4f(N4,5-N6,7N6,7) super-Coster-Kronig decay process in the excited states. It is shown that the lifetime broadening of the states in the multiplets strongly varies with their binding energies. The calculation considering the decay effect reproduces the experimental spectrum fairly well. The generally adopted assumption of the constant core-hole lifetime broadening breaks down completely if the coupling between a core-hole and unfilled valence shell is strong and yet the decay process is dominated by the coupling between them. The tendency in the lifetime broadening, that the larger binding energy states have the wider width, can be understood from a point of view of electron correlation. © 1994 The American Physical Society.