PHYSICOCHEMICAL STUDY OF THE SYSTEM BI2SE3-SMSBSE3

The chemical interaction in the Bi2Se3-SmSbSe3 system is investigated by the methods of physicochemical analysis (DTA, XRD, MSA, microhardness measurement and density determination), a state diagram is constructed. As a result, it was revealed that the state diagram of the system belongs to the quasi-binary eutectic type. In the Bi2Se3-SmSbSe3 system in a 1: 1 ratio of components, one triple compound of the composition SmSb1,5Bi1,5Se6 melting congruently at a temperature of 1150K is formed. According to the results of X-ray phase analysis, it was found that the SmSb1,5Bi1,5Se6 compound crystallizes in the tetragonal system with lattice parameters: a = 20.03 Å, c = 13.85 Å, z = 3, density ρpicn = 7.25 g/сm3, ρrent = 7 , 33 g/сm 3. On the basis of Bi2Se3, a region of solid solutions wыas found, which reach 6 mol% SmSb1,5Bi1,5Se6. In the Bi2Se3-SmSbSe3 system, a continuous series of solid solutions was found in the concentration range 050 mol% Bi2Se3 (SmSbSe3- SmSb1,5Bi1,5Se6). Compounds Bi2Se3 and SmSb1,5Bi1,5Se6 form a eutectic with a composition of 20 mol% Bi2Se3 at a temperature of 800K.