Revealing the local structure of CuMo$_{1-x}$W$_x$O$_4$ solid solutions by multi-edge X-ray absorption spectroscopy

• Published in: Materials Research Bulletin Vol. 153; p. 111910
• Main Authors: Pudza, Inga, Anspoks, Andris, Aquilanti, Giuliana, Kuzmin, Alexei
• Format: Journal Article
• Language: English; Japanese
• Published: arXiv 01.01.2022
• Subjects: Condensed Matter - Materials Science; CuMo1−xWxO4; FOS: Physical sciences; Materials Science (cond-mat.mtrl-sci); NATURAL SCIENCES::Physics [Research Subject Categories]; Physics - Materials Science; reverse Monte Carlo; solid solutions; X-ray absorption spectroscopy
• ISSN: 0025-5408
• DOI: 10.48550/arxiv.2205.13990

Mater. Res. Bull. 153 (2022) 111910 The effect of tungsten substitution with molybdenum on the structure of CuMo$_{1-x}$W$_x$O$_4$ ($x$ = 0.20, 0.30, 0.50, 0.75) solid solutions was studied by multi-edge X-ray absorption spectroscopy. The simultaneous analysis of EXAFS spectra measured at several (Cu K-edge, Mo K-edge and W L$_3$-edge) absorption edges was performed by the reverse Monte Carlo method taking into account multiple-scattering effects. The degree of distortion of the coordination shells and its dependence on the composition were estimated from partial radial distribution functions (RDFs) $g(r)$ and bond angle distribution functions (BADFs) $f(\varphi)$. The analysis of partial RDFs suggests that the structure of solid solutions is mainly determined by the tungsten-related sublattice, while molybdenum atoms adapt to a locally distorted environment. As a result, the coordination of both tungsten and molybdenum atoms remains octahedral as in CuWO$_4$ for all the studied compositions.