Excitons and Resonant Inelastic X-Ray Scattering in Graphite

Abstract
X-ray resonant inelastic scattering in graphite is analyzed including the effect of a screened core-hole Coulomb potential in the intermediate state. Numerical calculations of the scattered intensity are reported. Evidence for the presence of excitonic states in the observed K-edge spectra is provided, thus identifying a major drawback in the use of resonant scattering as a probe of electronic band structures.