Discrete-basis-function approach to electron-molecule scattering

The authors discuss two discrete-basis-function approaches to the soluion of the $T$-matrix equations for the scattering of electrons by atoms or molecules. Both methods, one of which is based on the Schwinger variational principle, have major advantages over the previously proposed $T$-matrix methods and do not require large-basis-set expansions. Results are reported for $s$- and $p$-wave scattering for helium.