The final state interaction in 3p-3d resonance excitation of Ni(111)

The change in the photoelectron energy distribution curve caused by the excitation energy change has been measured on Ni(1 1 1) in the excitation energy region from 40 to 115 eV. The MVV super Coster-Kronig (sCK) band has four features at 49.8, 56.3, 59.5, and 60.5 eV in kinetic energy. The excitation processes leading to the final state should be treated as a single process occurring simultaneously. The final states responsible for the sCK band and the two-hole bound state band appear to be independent of each other when the two bands are separated far apart. When they occur near to each other, the spectral shapes change and eventually the two bands merge into a broad band with inseparable features. Even in this band, a peak is found around a binding energy of 6.3 eV. The complete merger occurs at an excitation energy of 68 eV. The resulting single band is broader than the independent two-hole bound state band. Apparent peak shift occurs in a way similar to the case of the post-collision interaction in atomic spectra. (c) 2005 Elsevier B.V. All rights reserved.