0000000000411813
AUTHOR
J. Gaidelene
EXAFS study of mixed nickel molybdenum oxide thin films at the Ni and Mo K-edges
Mixed nickel molybdenum oxide thin films were produced by DC magnetron co-sputtering technique with the nickel content about 8, 16 and 25 at%. X-ray absorption spectroscopy at the Ni and Mo K-edges was used to study the local atomic structure in the films. The best-fit analysis of the EXAFS signals suggests that (i) the films are amorphous, except for the highest nickel content (25 at%), at which a segregation of NiO phase was observed; (ii) nickel and molybdenum atoms are octahedrally coordinated by oxygen atoms. Opposite to the NiO6 octahedra, the MoO6 octahedra are strongly distorted, that results in an existence of two groups of oxygen atoms—four nearest at B1.76 ( A and two distant at …
Influence of hydrogen intercalation on the local structure around Re ions in perovskite‐type ReO 3
octahedra with the Re-O-Re angle equal to 169° and the Re-O distance of about 1.90 A [9]. More accurate information on the local atomic and electronic structure of the bronzes can be ob-tained using XAS, which is a structural method complimentary to diffraction. To our knowledge, no such works have been performed until now. In this work, we present the first results of the in-situ XAS study of hydrogen intercalation into ReO
Oxygen K-edge x-ray absorption near-edge structure in crystalline and amorphous molybdenum trioxides
X-ray absorption near-edge structure (XANES) signals at the oxygen K edge in polycrystalline α-MoO3 and amorphous a-MoO3 thin film were analysed within the full-multiple-scattering (FMS) formalism. Significantly different XANES signals were found for non-equivalent oxygen atoms in low-symmetry layered-type α-MoO3 structure. The obtained results are in agreement with the experimental data and allow us to interpret all XANES peaks for α-MoO3. Besides, the FMS XANES simulations, performed for several fragments of α-MoO3 structure, allowed us to explain the O K-edge XANES in amorphous a-MoO3 thin film. We found that although the crystallographic structures of α-MoO3 and a-MoO3 are strongly diff…