The influence of Zn2+ ions on the local structure and thermochromic properties of Cu1-xZnxMoO4 solid solutions

Abstract

The influence of zinc ions on the thermochromic properties of polycrystalline Cu1−xZnxMoO4 (x=0.10, 0.50, 0.90) solid solutions was studied by X-ray absorption spectroscopy at the Cu, Zn and Mo K-edges. Detailed structural information on the local environment of metal ions was obtained from the simultaneous analysis of EXAFS spectra measured at three metal absorption edges using the reverse Monte Carlo method. Thermochromic phase transition with the hysteretic behaviour between α and γ phases was observed in Cu0.90Zn0.10MoO4 solid solution. It was found that the local environment of molybdenum ions is most susceptible to the substitution of copper for zinc and, upon cooling, transforms from tetrahedral MoO4 to distorted octahedral MoO6.