Calculation of Inelastic Electron-Molecule Collision Cross Sections by Classical Methods

We have used Thomson's, Gryzinski's, and Ochkur's classical methods for energy transfer in electronic collisions together with the quantum-mechanical Franck-Condon factor for the overlap of nuclear wave-functions to compute inelastic electron-molecule collision cross sections. Specific application is to ionization and to direct and exchange electronic excitation. After first extending previous applications of the classical energy-transfer methods to atoms, we make calculations for ionization, direct and exchange (spin-change) excitation involving air molecules (N(2), N(2)(+), NO, O(2), also CO). The results are applied to the near-threshold domain as well as to the over-all behavior of the cross section. Agreement with the very few absolute experimental data available is to within better than a factor of 2 to 3. These methods must be regarded as useful when one considers that there exist hardly any experimental data on excitation and that quantum-mechanical calculations would be prohibitively lengthy to carry out while the present calculations are very simple to perform.