Anomalous dielectric behaviour during the monoclinic to tetragonal phase transition in La(Nb0.9V0.1)O4. Issue 1 (11th November 2020)

• Record Type: Journal Article
• Authors: Zhou, Di; Guo, Huan-Huan; Fu, Mao-Sen; Yao, Xiao-Gang; Lin, Hui-Xing; Liu, Wen-Feng; Pang, Li-Xia; Singh, Charanjeet; Trukhanov, Sergei; Trukhanov, Alex; Reaney, Ian M.
• Is Part Of: Inorganic chemistry frontiers. Volume 8:Issue 1(2021)
• Page Start: 156
• Page End: 163
• Publication Date: 2020-11-11
• Subjects: Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/d0qi00981d
• Languages: English
• ISSNs: 2052-1553

Abstract

Abstract : The behaviour of ε r in La(Nb0.9 V0.1 )O4 vs. temperature is anomalous and may have novel applications in composite ceramics. Abstract : La(Nb0.9 V0.1 )O4 has been shown by in situ Raman spectroscopy and X-ray diffraction to undergo a ferroelastic phase transition from monoclinic fergusonite to tetragonal scheelite ( T M–T ) at 350 °C, accompanied by 3.55% spontaneous strain and an abrupt change in the thermal expansion coefficient ( α L ) from +15.5 ppm °C −1 to +11.4 ppm °C −1 . Assuming a linear relationship between polarizability and temperature, an anomalous decrease in relative permittivity ( ε r ) at T M–T is predicted from the Clausius–Mosotti relation and Shannon's additive rule. Such an anomalous decrease in ε r in a phase transition has not previously been observed in ferroic and linear dielectrics and may aid in the design of novel microwave dielectric composites.