Electron scattering by nitrogen molecules: Theory and application to elastic scattering and rotational excitation at 30–75 eV

Abstract

An effective potential model applicable to electron scattering by small or large molecules, including rotational and vibrational motions, is developed for electron scattering by N₂. The INDO/1s method is used to calculate the static potential at a large number of distances and a simple model is used for the polarization potential. The rotational and vibrational matrix elements of these potentials are accurately calculated and the scattering is treated by a truncated close‐coupling expansion. With no adjustable parameters, calculated electronically and vibrationally elastic scattering cross sections are in reasonable agreement with experiment for angles 40°–50° and less at energies 30–75 eV. The rotational excitation cross sections have never been measured for N₂ but are predicted to be large (as large as half the pure elastic cross sections when integrated over scattering angles and larger than the pure elastic differential cross sections at a range of large scattering angles at each energy).