Semi-Empirical Expressions Describing the Elastic Scattering of Slow Electrons by Molecules

Practical, semi-empirical expressions are proposed, which describe the differential cross sections (DCS) and cross sections (CS) for the elastic scattering of low energy (( 200 eV) electrons by various molecules (N2, H2O). These formalisms are partly based on the screened Rutherford formula, and completed by non-Rutherfordian terms whose parameters have been determined by fitting to experimental data from the literature. These parameters were expressed in terms of simple analytical functions of the electron's energy. A satisfactory accord has been obtained over the largest part of the angular domain covered.