Vacuum ultraviolet absorption spectrum of p-benzoquinone

Abstract

The vacuum ultraviolet absorption spectrum of p-benzoquinone measured by photometric and photographic techniques is reported. The valence transitions are assigned and the Rydberg absorptions analysed showing that both p and d series are present. This observation is interpreted as showing that the highest occupied molecular orbital of the molecule is localised on the ketone groups and that molecular core structure has to be explicitly considered in accounting for the series. Oscillator strength data are reported and shown to support the ketonic character of the Rydberg series.