Phase-shift problem in the study of the c(2 x 2)S/Ni(100) surface by surface extended x-ray-absorption fine-structure spectroscopy.

Abstract

The data analysis of the surface extended x-ray-absorption fine structure (SEXAFS) has been made for the c(2\ifmmode\times\else\texttimes\fi{}2)S/Ni(100) surface. A large and K-independent phase difference is found by the comparison of the theoretical phase shifts with the experimental ones. This phase difference can be explained as arising from the use of the plane-wave rather than the spherical-wave approximation in the EXAFS scattering theory.