Abstract
Compositional region, in which the "0212" structure is stabilized, was investigated in a (La1-ySry)2 (Ca1-xYx)Cu2Oz system. For ceramics at various x and y, crystal structure was examined by powder X-ray diffraction and electrical resistivity was measured by standard four-probe method. Almost single-phase ceramics were synthesized in the region of 1.0≥4y-x≥0.8. No monotonical change in lattice parameters with the values of x and y was observed. The sample obtained at a nominal composition of La1.4Sr0.6Ca0.8 Y0.2Cu2Oy (x=0.2, y=0.3) showed the lowest resistivity in all materials with the "0212" structure. No superconductor was found in the "0212" structure.
