Elastic electron scattering. II. Scattering from polyatomic potentials

A treatment of intramolecular multiple scattering in diatomic molecules is extended to cover the polyatomic case. The differential cross section is expressed as a sum of two and three atom interactions with the latter depending strongly on the geometrical arrangement. However, an interplay between the multiple scattering amplitudes for each three atom fragment ensures that all symmetry requirements of the entire molecule are satisfied. For illustrative purposes, cross sections for ten keV electrons are calculated for the fragments FF2 and FF3 to demonstrate the detailed character of the multiple scattering corrections.