Bm. Nestmann et al., R-MATRIX CALCULATION FOR ELECTRON METHANE SCATTERING CROSS-SECTIONS, Journal of physics. B, Atomic molecular and optical physics, 27(11), 1994, pp. 2297-2308
A recently developed technique for calculating cross sections in elect
ron-molecule collision processes based on variational R-matrix theory
is discussed. One of the main advantages of this method is its applica
bility to polyatomic systems. As a first example, integral and partial
cross sections for the e- + CH4 system below the ionization limit and
in the energy range of the Ramsauer minimum are presented. In additio
n, the corresponding eigenphases are shown. All calculations are based
on the fixed-nuclei approximation. The paper is concluded by an analy
sis of the Ramsauer minimum with respect to the angular dependency of
the differential cross sections in that energy region.