High-resolution excitation-energy-dependent study of the Auger decay of the O 1s-1πg core-excited state in oxygen -: art. no. 012719

We report new measurements of the decay of the core-excited O 1s-1 pi (g) (3)Pi (u) state in molecular oxygen under Auger resonant Raman conditions. The spectral features are interpreted with the aid of ab initio calculations using standard lifetime-vibrational interference, and in some cases, employing a model in which the bond-length dependence of the Auger transition rates is taken into account. By analyzing a series of Auger-decay spectra using different excitation energies, several instances of fixed kinetic energy are pointed out in the spectra; the nondispersive behavior arises from the decay between two potentials that are essentially parallel.