International Journal of Hydrogen Energy, Vol.26, No.5, 477-481, 2001
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 two methods of X-ray absorption spectroscopy XANES and EXAFS. Information about 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 the nearest absorption region (XANES) in WSe2. WO3 and HxWSe2, HxWO3. A possibility of investigation of changes in the atomic-crystalline structure during 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 sensibility of the EXAFS-method concerning small atom displacements in the WO3 and WSe2 compounds due to hydrogen insertion.
Keywords:EXAFS-method;hydrides;layered structure;X-ray absorption spectroscopy;metal-hydrogen bonds;ionic component