A comprehensive study of the vibrationally resolved S 2p −1 Auger electron spectrum of carbonyl sulfide

High-resolution normal Auger-electron spectra of carbonyl sulfide subsequent to S 2p−1 photoionization at photon energies of 200, 220, and 240 eV are reported along with corresponding photoelectron spectra. In addition, theoretical results are presented that take the core-hole orientation of the various spin-orbit-split and molecular-field-split S 2p−1 states into account. Auger transitions to eight metastable dicationic final states are observed and assigned on the basis of the theoretical results. From Franck-Condon analysis, assuming Morse potentials along the normal coordinates for seven of the observed quasi-stable dicationic final states, information on the potential-energy surfaces is derived and compared with theoretical results from the literature.