Offset-correctedΔ-Kohn-Sham scheme for semiempirical prediction of absolute x-ray photoelectron energies in molecules and solids

Absolute binding energies of core electrons in molecules and bulk materials can be efficiently calculated by spin paired density-function theory employing a Δ-Kohn-Sham (ΔKS) scheme corrected by offsets that are highly transferable. These offsets depend on core level and atomic species and can be determined by comparing ΔKS energies to experimental molecular x-ray photoelectron spectra. We demonstrate the correct prediction of absolute and relative binding energies on a wide range of molecules, metals, and insulators.