Geometric structure of (NaCl)4 clusters studied with XANES at the chlorine L-edge and at the sodium K-edge

X-ray absorption near edge structure (XANES) spectra at the sodium K-edge and chlorine L-edge of Na4Cl4 clusters have been studied. A theoretical ab initio analysis of XANES, based on full multiple scattering theory, is compared to experiment. To study the cluster geometry XANES spectra have been simulated for several different structural models including one obtained here from density functional theory (DFT). The results obtained show a significant dependence on the interatomic Na–Cl distance and also support a Td distortion from a perfect Na4Cl4 cube.