Theoretical evidence for short-lived resonances in electron scattering by HCl and HF molecules

The elastic scattering of electrons by HCl and HF, is theoretically examined within the fixed-nuclei, adiabatic approximation. It is possible to explain the behaviour exhibited by the HCl target in the 2-4 eV region by a broad resonance having 2 Sigma symmetry. Application of the same model to HF molecules fails to produce such a resonance. The important role played by the distortion of the molecular charge distributions caused by the incoming electron is discussed.