Absolute oscillator strengths for hydrogen sulphide - II. Ionic photofragmentation and photoionization in the valence shell continuum regions (10-60 eV)

Absolute oscillator strengths (cross sections) of ionic photofragmentation and photoionization for hydrogen sulphide in the valence shell continuum re gions have been determined using dipole (e,e + ion) coincidence spectroscop y (similar to 1 eV fwhm) at equivalent photon energies from the first ioniz ation threshold to 60.2 eV. These have been determined from the recently pu blished absolute photoabsorption oscillator strengths [Feng et al., Chem. P hys. 244 (1999) 127] together with the photoionization efficiency and ionic photofragmentation branching ratios obtained from time-of-flight mass spec tra reported in the present work. Consideration of the presently reported d ata together with the photoelectron branching ratios for H2S and ionization potentials obtained from previously reported photoelectron and dipole (e,2 e) spectroscopies yields quantitative information on the breakdown pathways of H2S following absorption of radiation in the VUV and soft X-ray regions . A new photofragmentation product (H-2(+)) and the doubly charged molecula r ion (H2S2+) from hydrogen sulphide have been found in the present work. P artial photoionization oscillator strengths for production of the four vale nce shell electronic states of H2S+ have also been derived from the molecul ar and dissociative partial photoionization oscillator strengths over the e ntire energy range up to 60.2 eV. (C) 1999 Elsevier Science B.V. All rights reserved.