Baginskiy I. Synthesis, structure and electrophysical properties of the solid solutions Ln1+xBa2-xCu3Oy.

The dissertation is devoted to studying of sol-gel synthesis of solid solutions Ln1+хBa2-хCu3Oy (Ln123), their crystal structure, oxygen stoichiometry and structure features effect on the superconducting transition temperature of Ln123. The optimal conditions for sol-gel synthesis of solid solutions Sm123 have been found. The dependences of lattice parameters and oxygen stoichiometry on the substitution ratio x and the treatment temperature were studied for the solid solutions Ln123. The oxygen ionic radii in the crystal lattice of Sm123 and widths of inter-ion spaces between oxygen ions in Sm123 were found using electron-positron annihilation method. The effect of the inter-ion spaces width on the critical temperatures of the solid solutions Sm123 was investigated.