Abnormal dielectric properties and phase transition in Bi₀.₇₈₃(Mo₀.₆₅V₀.₃₅)O₄ scheelite-related structured ceramic

摘要: In the present work, an interesting phase transition at 150 °C in ordered scheelite structured Bi₀.₇₈₃(Mo₀.₆₅V₀.₃₅)O₄ ceramic was observed for first time. This believed to be related arrangement of A site defects (or cations Bi³⁺). X-ray diffraction (XRD) and Raman spectra were employed study structure. Thermal expansion data showed that a sudden decrease cell volume during transition, which resulted sharp increase dielectric permittivity loss over wide frequency range (100 Hz 7.5 GHz). Far-infrared reflectivity THz used intrinsic properties. It found Bi–O stretches contributed mainly polarization. extended design materials knowledge their transitions.