|
|||||
|
|
XANES Determination of Chromium Oxidation States in Glasses: Comparison With Optical Absorption Spectroscopy |
|
| Authors: | Olivier Villain Georges Calas Laurence Gaioisy Laurent Cormier Jean-Louis Hazemann |
| Affiliation: | Institut de Minéralogie et de Physique des Milieux Condensés, UniversitéPierre et Marie Curie, UMR CNRS 7590, UniversitéDenis Diderot, Institut de Physique du Globe de Paris, 140 rue de Lourmel, 75015 Paris, France; Institut Néel, CNRS, UniversitéJoseph Fourier, 25 avenue des Martyrs, BP 166, 38042 Grenoble cedex 9, France |
| Abstract: | The oxidation state of chromium in glasses melted in an air atmosphere with and without refining agents was investigated by Cr K-edge X-ray absorption near-edge structure (XANES) and optical absorption spectroscopy. A good agreement in the relative proportion of Cr(III) and Cr(VI) is obtained between both methods. We show that the chemical dependence of the absorption coefficient of Cr(III) is less important in XANES than in optical absorption spectroscopy. The comparison of optical absorption and XANES spectra of glasses melted under different conditions provides an indirect assessment of the molar extinction coefficient of Cr(VI) in glasses. |
| Keywords: | |