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Magnetic behaviour of quasi-one-dimensional oxides, Ca$_3$Co$_(1+x)$Mn$_{1-x}$O$_6$

S. Rayaprol·Kausik Sengupta·E. V. Sampathkumaran
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Abstract

The results of ac and dc magnetization and heat capacity measurements on the oxides, Ca$_3$Co$_{1+x}$Mn$_{1-x}$O$_6$, forming in a K$_4$CdCl$_6$-derived rhombohedral quasi-one-dimensional crystal structure, are reported. As far as Ca$_3$Co$_2$O$_6$ is concerned, the results reveal 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 isothermal magnetization behavior.

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S. Rayaprol, Kausik Sengupta, E. V. Sampathkumaran. 2003-06-17. Magnetic behaviour of quasi-one-dimensional oxides, Ca$_3$Co$_(1+x)$Mn$_{1-x}$O$_6$. https://doi.org/10.1016/s0038-1098(03)00618-5

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