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.

Metastable states in NO2+ probed with Auger spectroscopy.

High-resolution N 1s and O 1s photoelectron spectra (PES) of NO are presented together with spectra of the subsequent Auger decay. The PES are analyzed by taking spin-orbit splitting of the (2)Π ground state into account providing detailed information on equilibrium distances, vibrational energies, and lifetime widths of the core-ionized states. In the Auger electron spectra (AES) transitions to five metastable dicationic final states are observed, with two of them previously unobserved. A Franck-Condon analysis of the vibrational progressions belonging to these transitions provides detailed information on the potential-energy curves of the dicationic final states as well as on the relative Auger rates. The present calculations of the potential-energy curves of NO(2+) agree well with the experimental results and allow an assignment of the two hitherto unresolved Auger transitions to excited states of NO(2+), C(2)Σ(+)and c(4)Π.