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Abstract: The inner valence electron spectrum of the CS2 molecule has been investigated in the binding energy range between 18.6 and 26.3eV using synchrotron radiation for ionisation. Photon energies in the range from 67 to about 167eV have been used, with particular focus on 166.70, 166.89 and 167.09eV for which S2p electrons are resonantly transferred into Rydberg orbitals close to the ionisation threshold. From there, autoionisation takes the molecule into various cationic states characterized by two valence holes and a Rydberg spectator electron. Many new bands are observed which contain vibrational progressions with spacings around 120meV in most cases. These are assigned as excitations of the totally symmetric stretching ν 1 mode in the cationic state. The new bands reflect states in the cation that are close to the electronic states of the dication and assignments are made by comparison to double ionisation electron spectra. [Copyright &y& Elsevier]

Abstract: The recently discovered emission has been investigated experimentally and theoretically, leading to the identification of two separate fluorescent dicationic transitions ( and 11Δg ←11Δu). The vertical energies of the fluorescent electronic states were directly obtained by detecting photons in coincidence with electron pairs. Their assignment was aided by the use of glass filters to isolate the spectral region of each emission and by performing highly correlated MRCI calculations at a range of geometries. The potential energy curves thus generated predict bound potential energy functions for all linear Σ and Δ states of triplet and singlet spin multiplicities, throughout the energy range studied. Dissociation onsets for different fragmentation pathways are re-evaluated by detecting ions in coincidence with electron pairs. The C+ +S+ onset is revised downwards to 36.8±0.4eV and formation is found to arise from non-statistical dissociation of a limited number of precursor states, which have been identified to be the electronically excited formed in bent structures at these internal energies. Assignments have been attempted for all fragment emissions observed by measuring quantum yields as a function of the selected spectral region. [Copyright &y& Elsevier]