Ab Initio Inclusion of Electron-Hole Attraction: Application to X-Ray Absorption and Resonant Inelastic X-Ray Scattering

This work demonstrates a numerically feasible, yet realistic, calculational method for incorporating electron-core-hole interactions (core-hole effects) in the Bethe-Salpeter equation in solids, without recourse to tight-binding or analogous basis-set approximations. The method includes ab initio treatments of separate electron and hole dynamics and electron-hole interactions. The method is used to treat x-ray absorption (XAS), resonant inelastic x-ray scattering (RIXS), and core-hold excitons. Materials studied include LiF, NaF, KF, graphite, diamond, and $h-\mathrm{BN}$.