Breakdown of the One-Electron Picture in XPS, XES and AES Spectra Involving 4s and 4p Holes in 46Pd to 54Xe

Abstract

The 4s-1–4p-1 XPS and Lγ2, 3(2s-1→4p-1) XES spectra of the elements 46Pd to 54Xe have been calculated from first principles by diagrammatic many-body theory within the framework of a free atom calculation1,2 . Both the XPS and XES spectra show breakdown of the one-electron picture or, more generally the quasi-particle picture (Q.P.P.), of a 4p hole due to strong dynamical giant-Coster Kronig (gCK) 4p-1 ↔ 4d-2 m, ef fluctuation and decay processes. For a 4s hole there is a large energy shift from the ASCF positions due to gCK fluctuation 4s ↔ 4p-1 4d-1 ef. However, an effective one-electron picture (Q.P.P.) of a 4s hole is valid.