Phase transitions, structure and properties of solid solutions V_{2 – Δ}ME_0,02O₃

Abstract

Subject of research: the article presents studies of the properties of solid solutions V2Me0,02O3 in the metaldielectric phase transition region. Purpose of research: to obtain temperature dependences of physical parameters (heat capacity, electrical resistance, magnetic susceptibility) of samples of the composition V2Me0,02O3 in the range of 60-400 K; to determine the effect of vanadium concentration and the type of alloying element on the parameters of the phase transition and the parameters of the energy spectrum of the crystal lattice. Methods and objects of research: the objects of research were solid solutions based on vanadium oxide V2O3, alloyed with aluminum, iron, chromium. Doping was used to regulate and stabilize the parameters of the V2O3 phase transition. The temperature of the phase transition was determined by measuring the temperature dependences of heat capacity, electrical resistance and magnetic susceptibility. Main results of research: in the course of experimental studies, it was found that the temperatures of metaldielectric phase transitions determined by different methods are close in their values. The dependences of the phase transition temperature on the parameters of the crystal lattice, changes in magnetic susceptibility for pure and doped vanadium oxide, as well as the dependence of the transition temperature and the electrical resistivity jump on the Debye temperature are obtained. The influence of alloying metals and vanadium concentration on the properties of the studied samples in the phase transition region was determined by the temperature dependences of magnetic susceptibility, electrical resistance and heat capacity.