Akademik Məlumat İdarəetmə Sistemi
Journal of Alloys and Compounds, vol.1036, 2025 (SCI-Expanded, Scopus)
Phase equilibria in the MnSe–Ga2Se3–In2Se3 system were studied by differential thermal analysis, X-ray diffraction analysis, and scanning electron microscopy techniques. A number of polythermal and isothermal sections of the phase diagram, as well as a projection of the liquidus surface were constructed. The fields of primary crystallization of seven phases, as well as, the types and coordinates of in- and monovariant equilibria in the system were determined. It was shown that wide solid solution areas formed on the MnGa2Se4–MnIn2Se4 section expand significantly towards the boundary system Ga2Se3–In2Se3 and result in large homogeneous areas. The homogeneity regions based on Ga2Se3 extend significantly—over 40 mol%—into the composition triangle, forming a broad homogeneity area. As part of this study, the boundary quasi-binary system MnSe–In2Se3 was re-investigated, and a new phase diagram, markedly different from that reported in the literature, was constructed. It was found that the system forms a congruently melting MnIn2Se4 compound at 1193 K and an incongruently melting Mn2In2Se5 compound at 1196 K via a peritectic reaction. MnIn2Se4 has a wide homogeneity area. Based on the powder diffraction patterns, the crystal structures of both compounds were determined and their lattice parameters were refined by the Rietveld method. The study of the temperature dependence of electrical conductivity and the volt-ampere characteristics of the MnGaInSe4 compound revealed that the current flow in the nonlinear region of the current-voltage curve corresponds to Frenkel's theory of thermoelectric ionization. The concentration of ionized centers in this crystal (Nt =9·1014 cm−3), the mean free path of charge carriers (λ1= 7.3·10−5 cm) and the shape of the potential well of traps were determined. The activation energy of the charge carriers was determined from the temperature dependence of the electrical conductivity of the MnGaInSe4 crystal (E = 0.30 eV).