Theoretical study on intensities in the discrete and continuum electronic spectrum of acetone

•The absorption spectrum of acetone in the VUV arises mainly from Rydberg states.•Spectral intensities are calculated with the molecular quantum defect orbital method.•Oscillator strengths for ns and nd Rydberg series are reported.•Cross-section profile for the production of (CH3)2CO+ in its ground state is shown.•The method is suitable to predict intensities in both discrete and continuum regions.

Intensities, expressed as oscillator strengths for the discrete and, as cross-sections for the continuum electronic spectrum of acetone are reported. The calculations have been performed with the molecular quantum defect method (MQDO), which has proved to be a very adequate tool for this type of studies in other organic molecules. The present work covers transitions to more highly excited Rydberg states than had previously been reported. The quality of the oscillator strengths has been assessed by comparison with scarce data available in the literature, and by its compliance with the expected trends along the Rydberg series. Electronic partial photoionization cross-sections for acetone over the 10-50 eV photon energy are also calculated. Cross-section profiles for Rydberg series that constitute the ionization channels of acetone from the outermost orbital in its ground state are reported for the first time.