Open AccessXANES analysis of spectral properties and structures of arsenate adsorption on TiO 2 surfaces
Author(s) -
He Guangzhi,
Pan Gang,
Zhang Meiyi
Publication year - 2012
Publication title -
journal of synchrotron radiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 99
ISSN - 1600-5775
DOI - 10.1107/s0909049512008059
Subject(s) - xanes , scattering , arsenate , adsorption , absorption (acoustics) , extended x ray absorption fine structure , spectral line , chemistry , materials science , amplitude , chemical physics , analytical chemistry (journal) , crystallography , absorption spectroscopy , optics , arsenic , physics , composite material , organic chemistry , astronomy
X‐ray absorption near‐edge structure (XANES) of arsenate adsorption on TiO 2 surfaces was calculated using self‐consistent multiple‐scattering methods, allowing a structural analysis of experimental spectra. A quantitative analysis of the effect of disorder revealed that the broadening and weakening of the characteristic absorption in experimental XANES was due to the structural disorder of the arsenate–TiO 2 adsorption system. The success with calculating the scattering amplitude of a specific set of paths using the path expansion approach enables the scattering contributions of different coordination shells to the XANES to be sorted out. The results showed that the scattering resonances from high‐level shells inherently overlapped onto the first‐shell scattering amplitudes, and formed the fine structures in the XANES region. A variation in one oscillatory feature could be due to several structural changes affecting specific single/multiple‐scattering amplitudes. Therefore, direct assignments of spectral features with structural elements should be based on adequate theoretical analysis.