Full Multiple Scattering Approach to X-Ray Absorption near Edge Structure Spectra of Bromonaphthalene in Supercritical Xenon

Detailed X-ray absorption near edge structure (XANES) analyses are carried out in order to study the local structure around a Br atom of bromonaphthalene dissolved in supercritical fluid Xe by usage of full multiple scattering calculations. We find that about six Xe atoms surround the Br atom at the distance of about 5 A, which is larger than the sum of the van der Waals radii (4.15 A). Other important information is the relative thermal fluctuation (Debye-Waller factor) between Br and Xe, which is quite large, ~0.8 A. This large thermal fluctuation and clustering are essential characteristic features of supercritical systems.