Non-Perturbative Quantal Methods for Electron–Atom Scattering Processes

Abstract

In just over a decade, a number of non-perturbative close-coupling methods have been developed that are capable of very accurate calculations of electron–atom collisions. For electron collisions with hydrogen-like targets, one of the most important three-body Coulomb problems, they are limited only by the accuracy of the two-electron continuum and the completeness of the partial-wave expansion; for multielectron systems, the accuracy of the target description is normally the limiting factor. Here we consider two non-perturbative methods: the R-matrix with pseudo states (RMPS) method and the time-dependent close-coupling (TDCC) method. We present descriptions of both of these methods and consider their application to electron-impact excitation and ionization.