VIBRATIONALLY ELASTIC AND INELASTIC-SCATTERING OF ELECTRONS BY HYDROGEN-SULFIDE MOLECULES

Vibrationally elastic and inelastic cross sections (differential and i ntegral ones) are calculated for electron scattering from hydrogen sul phide (H2S) at the collision energies 3-30 eV. Vibrational excitation of all three fundamental modes is considered. The calculation is based on the rotationally sudden and a vibrationally close-coupling method using an ab initio electrostatic potential. The effects of electron ex change and target polarization are taken into account approximately. T he resulting cross sections are compared with the experimental data av ailable. The present differential cross sections (DCS) for the elastic scattering reproduce the experimental data well. For the inelastic sc attering, the present DCS is too small at 3 eV, compared with the expe rimental data. This is probably due to a shape resonance, which the pr esent calculation would not be sufficiently accurate to produce. In th e higher energy region (i.e. above about 10 eV), the present vibration al cross section should be more reliable, but no experimental data are available so far.