title: Theoretical study of the non-local optical potential in EXAFS spectra.
abstract: We study the optical potential effects on the extended x-ray absorption fine structure (EXAFS) and x-ray photoelectron diffraction (XPD) spectra. For the valence electron optical potential we use a local density approximation because the charge density changes fairly slowly, whereas we use a non-local optical potential for the core electron part based on GW-approximation. In the Br K-edge EXAFS spectra the present optical potential gives rise to the phase difference and the amplitude reduction; the agreement with the experimental result is excellent. In the N-1s XPD spectra for N2/Ni(100), the spherical wave effects enhance the effects due to the optical potential.
authors.affiliation: Graduate School for Science, Chiba University, Inage, Japan. hatada@scichem.s.chiba-u.ac.jp
authors.forename: K
authors.initials: K
authors.lastname: Hatada
authors.forename: T
authors.initials: T
authors.lastname: Fujikawa
authors.forename: L
authors.initials: L
authors.lastname: Hedin