Absolute oscillator strengths for hydrogen sulphide: I. Photoabsorption in the valence-shell and the S 2p and 2s inner-shell regions (4-260 eV)

Absolute photoabsorption oscillator strengths (cross-sections) for the valence-shell discrete and continuum regions of hydrogen sulphide from 4 to 30 eV have been measured using high-resolution (similar to 0.05 eV fwhm) dipole (e, e) spectroscopy. A wide-range spectrum, covering both the valence shell and the S 2p and 2s inner shells, has also been obtained from 5 to 260 eV at low resolution (similar to 1 eV fwhm), and this has been used to determine the absolute oscillator strength scale using valence-shell TRK (i.e., S(0)) sum-rule normalization. The presently reported high- and low-resolution absolute photoabsorption oscillator strengths are compared with previously published data from direct photoabsorption measurements. In addition, a dipole sum-rule analysis on the present photoabsorption data has been performed. The static dipole polarizability for hydrogen sulphide determined from the S(-2) sum-rule using the presently reported oscillator strengths is compared with previously reported polarizability values. Other dipole sums S(u) (u = -1, -3 to -6, -8, -10) and logarithmic dipole sums L(u) (u = -1 to -6) are also determined from the presently reported absolute photoabsorption differential oscillator strengths. (C) 1999 Elsevier Science B.V. All rights reserved.