Nonperturbative electron-ion scattering theory incorporating the M{\o}ller interaction

Relativistic distorted wave studies by Fontes's etal~[\textit{Phys.~Rev.~A} {\textbf{47}}, 1009 (1993)] demonstrated that the Generalized Breit interaction (equivalently the M{\o}ller interaction) can affect electron-impact excitation cross sections of hydrogenlike ${\rm U}^{91+}$ by more that 50\% in comparison to calculations that employ the Coulomb interaction alone. We present the first calculations that investigate the effects of both the M{\o}ller interaction and close-coupling in the calculation of electron-impact excitation cross sections~[1]. Electron scattering from ${\rm U}^{91+}$ is used as a test case. The RCCC method is nonperturbative and we emphasise the restrictions and subsequent limitations associated with employing the M{\o}ller interaction in the RCCC method. \\[4pt] [1] C. J. Bostock, D. V. Fursa, and I. Bray, Phys. Rev. A 86, 042709 (2012).