X-ray spectroscopy investigation of hydrogen-containing phases based on the compounds of tungsten with VI group elements

New data on both electronic and atomic structures of hydrogen bronze, HxWO3 , and a compound HxWSe2 with a layered structure have been obtained using t wo methods of X-ray absorption spectroscopy XANES and EXAFS. Information ab out interatomic interaction. metal-hydrogen bonds and their ionic component has been obtained by means of an investigation of positions and shapes of the LIII-absorption edge of tungsten and K-absorption edge of selenium in t he nearest absorption region (XANES) in WSe2. WO3 and HxWSe2, HxWO3. A poss ibility of investigation of changes in the atomic-crystalline structure dur ing transformation WO3 double right arrow HxWO3 and WSc2 double right arrow HxWSe2 was tested, studying changes of the extended fine structure (EXAFS) of the X-ray L-III-absorption spectra of tungsten and K-absorption spectra of selenium. The analysis of spectra fine structure indicates a sensibilit y of the EXAFS-method concerning small atom displacements in the WO3 and WS e2 compounds due to hydrogen insertion. (C) 2001 International Association for Hydrogen Energy. Published by Elsevier Science Ltd. All rights reserved .