Nonadiabatic Theory of Electron-Hydrogen Scattering. II

Abstract

The triplet $S$-wave electron-atomic hydrogen elastic scattering phase shifts are recalculated by a previously introduced nonadiabatic theory. The previous calculation has been improved in a number of respects the most important of which is the utilization of noniterative technique for numerically solving the partial differential equations. (This technique is expected to be useful for a large class of linear second-order elliptic partial differential equations.) Phase shifts are computed to better than four significant figures. The results are quite close to the variational results of Schwartz but on the whole somewhat larger. The deviations are considered significant, and the various approaches are discussed. Specifically our triplet scattering length (in Bohr radii) is $a_t=1.7683\mathrm{}$, with an extrapolated value $a_t=1.767\mathrm{}$.