Kadykalo E. Phase equilibria and the properties of phases in the systems Ag2Se-CdSe-Ga2Se3, Cu2Te-CdTe-In2Te3.

The thesis contains the results of studies of the interaction of components in quasi-ternary systems Ag2Se-CdSe-Ga2Se3 and Cu2Te-CdTe-In2Te3. Quasi-ternary system Ag2Se-CdSe-Ga2Se3 was investigated by physico-chemical analysis methods for the first time. Phase diagrams of two quasi-binary systems, 7 polythermal sections, isothermal section at 820 K, liquidus surface projection and the spatial phase diagram were constructed. The existence of homogeneity regions of the system components and the intermediate phases at 820 К was investigated. The existence of the quaternary compound AgCd2GaSe4 was found in the system. Quasi-ternary system Cu2Te-CdTe-In2Te3 was investigated by differential thermal and X-ray phase analysis methods. Phase diagram of the boundary quasi-binary system Cu2Te-In2Te3, six polythermal sections, isothermal section at 670 K, liquidus surface projection and the spatial phase diagram were constructed. The existence of six homogeneity regions of binary and ternary system components at 670 К was determined. Single crystals of solid solutions with the sphalerite structure which form in the CuInTe2-CdTe system were grown for the first time by the directed crystallization of the melt. Band gap energy was estimated for the first time, and IR spectroscopy investigation was performed. Based on obtained results, suitable fields of application of these materials were suggested.