Abstract
The solid solution sanmartinite (ZnWO4)—cuproscheelite (CuWO4) has been studied using Cu 2p X-ray absorption spectroscopy. While a single L3 absorption peak is observed for CuWO4, two distinct L3 absorption peaks with a separation of ∼0.8 eV are observed for the intermediate samples in the solid solution. The two peaks represent distinct Cu sites: one with all CuO6 next nearest neighbours in the (Cu,Zn)O6 chains, another having at least one ZnO6 next nearest neighbour. Both sites show a linear increase in covalency as a function of increasing Cu-content. The relative intensities of the two absorption peaks is dependent upon the Cu-content and has been used to model the site occupancies. The results reveal that the local structural effects can be associated with a composition-dependent structural phase transition from P2/c (ZnWO4) to P \(\bar 1\) (CuWO4). Deviations from a single-site model are explained in terms of the local environments, and evidence for site preferences and local clustering are explored.
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Schofield, P.F., Henderson, C.M.B., Redfern, S.A.T. et al. Cu 2p absorption spectroscopy as a probe for the site occupancy of (ZnxCu1−x)WO4 solid solution. Phys Chem Minerals 20, 375–381 (1993). https://doi.org/10.1007/BF00203106
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DOI: https://doi.org/10.1007/BF00203106