Ba2(RE)Cu3O7−δ(RE=La, Pr, Nd, Sm, Gd): Crystal growth, structure and magnetic properties

A novel procedure for growing single crystals of the title phases has been found by dissolving (RE) 2 CuO 4 in appropriate liquid mixtures of BaO-CuO. The soaking conditions are, in each cases, different and the crystals were further annealed in pure oxygen. Symmetry, contamination from the crucible and superconducting properties are related to the growth conditions which are presented and discussed. Magnetic susceptibility measurements have been carried out down to 4.2 to both determine T c and the oxidation states of the rate earths.