Core hole and surface excitation correction parameter for XPS peak intensities

► We calculate surface excitations and excitations from the core hole in XPS. ► We introduce the Correction Parameter for XPS (CPXPS) for both effects. ► Calculations are performed within the dielectric response theory (QUEELS-XPS). ► CPXPS values are larger for oxides than for metals and semiconductors. ► This behavior is due to wave vector dispersion of the energy loss function.