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Study of Magnetic Properties of A_2B^'NbO_6 (A=Ba,Sr, (BaSr): and B^'=Fe and Mn) double perovskites

N. Rama·J. B. Philipp·M. Opel·K. Chandrasekaran·V. Sankaranarayanan·R. Gross·M. S. Ramachandra Rao
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Abstract

We have studied the magnetic properties of Ba_2FeNbO_6 and Ba_2MnNbO_6. it is seen that Ba_2FeNbO_6 is an antiferromagnet with a weak ferromagnetic behaviour at 5K while Ba_2MnNbO_6 shows two magnetic transitions one at 45 K and the other at 12K. Electron spin resonance (ESR) measurements at room temperature show that the Mn compound does not show any Jahn-Teller distortion. It is also seen that the Neel temperature of the A_2FeNbO_6 (A=Ba,Sr, BaSr) compounds do not vary significantly. However variations in the average A-site ionic radius influence the formation of short range correlations that persist above T_N.

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N. Rama, J. B. Philipp, M. Opel, K. Chandrasekaran, V. Sankaranarayanan, R. Gross, M. S. Ramachandra Rao. 2004-05-24. Study of Magnetic Properties of A_2B^'NbO_6 (A=Ba,Sr, (BaSr): and B^'=Fe and Mn) double perovskites. https://doi.org/10.1063/1.1682952

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