Y-P Sun, Annette Pietzsch, Franz Hennies, Z. Rinkevicius, Hans O. Karlsson, Thorsten Schmitt, Vladimir N. Strocov, Joakim Andersson, B. Kennedy, J. Schlappa, Alexander Föhlisch, F. Gel'mukhanov, Jan-Erik Rubensson
- Resonant inelastic soft x-ray scattering spectra excited at the dissociative 1 sigma(g) -> 3 sigma(u) resonance in gas-phase O(2) are presented and discussed in terms of state-of-the-art molecular theory. A new selection rule due to internal spin coupling is established, facilitating a deep analysis of the valence excited final states. Furthermore, it is found that a commonly accepted symmetry selection rule due to orbital parity breaks down, as the core hole and excited electron swap parity, thereby opening the symmetry forbidden 3 sigma(g) decay channel.
