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

► The M 4,5–N 2,3N 2,3 Auger-electron spectroscopy (AES) spectrum of atomic Sn is calculated by an ab initio atomic diagramatic perturbation theory. ► The AES spectrum is entirely smeared out and in good agreement with experiment. ► It shows the complete breakdown of the quasi-particle picture of the two N 2,3 holes by the N 2,3N 2,3–N 4,5N 4,5N 4,5N 4,5 and N 2,3N 2,3–N 2,3N 4,5N 4,5 super Coster–Kronig (sCK) transitions. ► By measuring the M 4,5 photoelectron spectroscopy (PES) spectrum in coincidence with the M 4,5–N 2,3N 2,3 Auger decay one can detect the missing M 4,5–N 2,3N 2,3 AES lines. The M 4,5–N 2,3N 2,3 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 M 4,5–N 2,3N 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 N 2,3N 2,3–N 4,5N 4,5N 4,5N 4,5 and N 2,3N 2,3–N 2,3N 4,5N 4,5 super Coster–Kronig (sCK) transitions. The present theory shows that one should be able to detect the missing M 4,5–N 2,3N 2,3 AES lines by measuring the M 4,5 photoelectron spectroscopy (PES) spectrum in coincidence with the M 4,5–N 2,3N 2,3 Auger decay. The lifetime width of the two N 2,3 holes is much larger than the effective Coulomb hole–hole interaction energy U between the two N 2,3 holes so that the multiplet coupling between the two N 2,3 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).