Isotope effects in vibrational excitation and dissociative electron attachment of DCl and DBr

The results of calculations of vibrational excitation and dissociative electron attachment cross-sections of DCl and DBr are reported. The calculations are based on the nonlocal resonance model for electron-HCl/HBr scattering. The cross-sections for many initial rovibrational target states were calculated both for the hydrogenated and the deuterated compounds. The calculations reveal an unexpected result: the vibrational excitation cross-section of the deuterated molecule may in some cases be (significantly) larger than that of the hydrogenated compound. This effect is observed when the target molecule is initially excited to a vibrational state the energy of which is close to the threshold of dissociative attachment. Rotational excitation of the target molecule plays a similar role. Isotope effects in dissociative electron attachment are also discussed.