Momentum dependence in K -edge resonant inelastic x-ray scattering and its application to screening dynamics in CE-phase La0.5 Sr1.5 MnO4

We present a formula for the calculation of K-edge resonant inelastic x-ray scattering on transition-metal compounds, based on a local interaction between the valence shell electrons and the 1s core hole. Extending a previous result, we include explicit momentum dependence and a basis with multiple core-hole sites. We apply this formula to a single-layered charge-, orbital-, and spin-ordered manganite, La0.5Sr1.5MnO4, and obtain good agreement with experimental data, in particular with regards to the large variation of the intensity with momentum. We find that the screening in La0.5Sr1.5MnO4 is highly localized around the core-hole site and demonstrate the potential of K-edge resonant inelastic x-ray scattering as a probe of screening dynamics in materials.