Synthesis and magnetism of Pr-based rutheno-cuprate compound RuSr2PrCu2O8-delta

We have successfully synthesized RuSr2PrCu2O8-delta in an essentially singl e-phase form. Structural analysis from room-temperature powder neutron diff raction pattern shows that this compound crystallizes in tetragonal Ru-1212 structure (space group P4/mmm). Magnetization measurements show clear bran ching of zero-field-cooled and field-cooled magnetization around 150 K indi cating magnetic ordering below this temperature (presumably associated with Ru moments), similar to that reported for RuSr2GdCu2O8-delta Magnetization versus applied field hysteresis loops indicate presence of a small ferroma gnetic component at 5 K. Though magnetic behaviour of RuSr2PrCu2O8-delta is similar to that of reported magneto-superconductor RuSr2GdCu2O8-delta, the Pr-based compound is non-superconductive down to 5 K. Results of presently studied RuSr2PrCu2O8-delta compound are compared with reported data on bot h superconductive and non-superconductive RuSr2GdCu2O8-delta samples. (C) 2 001 Elsevier Science B.V. All rights reserved.