X-ray absorption and Raman spectroscopy studiesof tungstates solid solutions Zn_cNi_1-cWO₄(c = 0.0-1.0)

The influence of thermal disorder and static distortions on the local structure in microcrystalline solid solu-tions of tungstates ZncNi1-cWO4 with c = 0.0-1.0 was investigated using temperature-dependent (10-300 K) X-ray absorption spectroscopy (XAS) at the W L3-edge. In addition, the vibrational properties of the solid solu-tions were studied by Raman spectroscopy. Our results indicate that the formation of solid solutions is accompa-nied by strong structural relaxations leading to the changes in the [WO6] octahedra distortions, which, in turn,affect the vibrational properties of tungstates. In particular, the frequency and band width of the highest W-Ostretching mode at about 900 cm^-1show distinct composition dependence, following the local structure modifi-cations as revealed by XAS.