Magnetic behaviour of quasi-one-dimensional oxides, Ca₃Co_1+xMn_1−xO₆

Abstract

The results of ac and dc magnetization and heat capacity measurements on the oxides, Ca₃Co_1+xMn_1−xO₆, forming in a K₄CdCl₆-derived rhombohedral quasi-one-dimensional crystal structure, are reported. As far as Ca₃Co₂O₆ is concerned, the results reveal a truly complex nature of the two magnetic transitions, identified to set in at 24 and 12 K in the previous literature. However, partial replacement of Co by Mn apparently results in a long magnetic ordering of an antiferromagnetic type (below 13 and 18 K for x=0.0 and 0.25, respectively), instead of spin-glass freezing in spite of the fact that there is Co-Mn disorder; in addition, interestingly there are hysteretic spin reorientation effects as revealed by the isothermal magnetization behavior.