Single and Multiple Electron Scattering Description in X‐Ray Absorption Spectrum Theory and the Problem of Solid Structure Investigation

The effect of photoelectron double and threefold scattering processes on XANES (in KCl K K‐spectrum, in BaTiO3 Ti K‐spectrum) and EXAFS (in Re L3‐spectra in ReO3 at various pressures) are investigated within the spherical wave formalism. The main contributions into the near edge absorption cross‐sections are shown to be due to the photoelectron scattering processes in the approximately linear atomic chains originating and terminating at the absorbing atom. The results obtained for EXAFS show good agreement with the experiment that enables one to solve the bondangle determination problem by EXAFS.