Electron population analysis by full-potential X-ray absorption simulations

We present the first successful attempt at calculating cluster full-potenti al x-ray absorption near-edge structure (XANES) spectra, based on the finit e difference method. By fitting XANES simulations onto experimental spectra we are able to perform electron population analysis. The method is tested in the case of Ti K-edge absorption spectrum in TiO2, where the amount of c harge transfer between Ti and O atoms and of the screening charge on the ph otoabsorber is obtained taking into account both dipolar and quadrupolar tr ansitions.