Absolute photoabsorption and photoionization studies of large polyatomic molecules by high energy electron impact and mass spectrometry

Electronic excitation spectra and absolute differential oscillator strengths (cross sections) have been measured from the visible up to the soft X-ray energy regions (2-200 eV) for the valence-shell photoabsorption of a series of normal alkanes (;The feasibility of using atomic and molecular mixture rules as well as group additivity concepts for predicting differential oscillator strengths for the valence-shell photoabsorption of long-chained alkane molecules has been investigated over a wide energy range from 20 to 200 eV. The predictions are discussed with reference to the experimental measurements for the normal alkanes obtained in the present work (C;Dipole (e,e + ion) coincidence spectroscope has been used to obtain the photoion branching ratios and absolute photoionization efficiencies of the valence shells of C...