Negative ion formation, vibrational excitation, and transmission spectroscopy in hydrogen halides

摘要: Three independent experiments are performed in order to elucidate low‐energy electron collisions on hydrogen halides. The formation of Cl− and Br− shows a steep onset near threshold structure at higher energies. This occurs the energies vibrational levels X 1Σ+ ground state halide. transmission spectrum HBr position v=1 level state. In addition, spectra show that cross section all halides rises steeply off about 60 meV above threshold. A trapped‐electron experiment HCl substantiates this observation gives magnitude (2×10−16–2×10−15 cm2).