An experimental and theoretical study of the valence shell photoelectron spectrum of sulphur dioxide Original Research Article

The complete valence shell photoelectron spectrum of sulphur dioxide has been studied using HeI, HeII and synchrotron radiation. The high resolution HeI and HeII excited spectra have allowed a detailed analysis to be made of the vibrational structure exhibited in the photoelectron bands associated with ionisation from the outer valence orbitais. A new satellite band containing vibrational structure has been observed around 19 eV. The photoelectron spectra recorded with synchrotron radiation demonstrate that the inner valence region contains several complicated structures and is dominated by a prominent feature centred at a binding energy around 34 eV. Many-body Greenʹs function calculations have been performed to evaluate the energies and pole strengths associated with the main lines and satellite states distributed throughout the valence shell region, and an interpretation of some of the experimental features is proposed, based upon these predictions.