Missing Auger electron emission lines of metallic Sn and Auger-photoelectron coincidence spectroscopy (APECS)

摘要

The M4,5-N2,3N2,3 Auger-electron spectroscopy (AES) spectrum of atomic Sn is calculated by an ab initio atomic diagramatic perturbation theory, i.e., the extended frozen core random phase approximation with exchange (RPAE). The AES spectrum is entirely smeared out and in good agreement with the experimental M4,5-N2,3N 2,3 AES spectrum of metallic Sn showing no discernible structure. It shows the complete breakdown of the quasi-particle picture of the two N 2,3 holes by the N2,3N2,3-N4,5N 4,5N4,5N4,5 and N2,3N 2,3-N2,3N4,5N4,5 super Coster-Kronig (sCK) transitions. The present theory shows that one should be able to detect the missing M4,5-N2,3N2,3 AES lines by measuring the M4,5 photoelectron spectroscopy (PES) spectrum in coincidence with the M4,5-N2,3N2,3 Auger decay. The lifetime width of the two N2,3 holes is much larger than the effective Coulomb hole-hole interaction energy U between the two N2,3 holes so that the multiplet coupling between the two N2,3 holes breaks down. This is analogous to the case when U between two holes created in valence band states is much smaller (or larger) than the bandwidth, the two holes are delocalized (or localized).