Solvation Structure of Chloride and Iodide Ions Studied by Means of Exafs Using a Compact Synchrotron Radiation Source

Abstract

An EXAFS (extended X-ray absorption fine structure) beamline set in a compact synchrotron radiation (SR) source at the SR Center of Ritsumeikan University consists of three windows, a slit, a double—crystal monochromator and two detectors. By using Si(220), Ge(220), and InSb(111) monochromator crystals, the EXAFS spectrometer covers the K—edge absorption energies of elements from silicon to zinc. Structural investigation of solvated ions with relatively low atomic numbers became possible under an atmospheric pressure. The EXAFS data of chloride and iodide ions in water, methanol and ethanol measured by the EXAFS equipment are reported. This is the first case to study the solvation structure of chloride ions by EXAFS.