Dissociative electron attachment on H2S: energy and angular distributions of H-ions

The authors have studied energy and angular distributions of H - ions produced by dissociative attachment on H 2 S in the 4.5-9 eV region by means of an electron impact spectrometer. H - formation proceeds via two distinct reactions. For the first one, the HS fragments, associated with the H - ions, are weakly vibrationally excited and the fraction of H - ions associated with the excited HS fragments increases with the incident electron energy. It is also shown that the H - ions associated with HS v=0 and those associated with HS v=1 fragments have different angular distributions. In the energy range of the second reaction, the HS fragments are in the ground vibrational state. In both cases, the HS fragments are found to be rotationally excited.