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arXiv · 0810.0667

Synthesis and characterization of multiferroic BiMn$_7$O$_{12}$

F. Mezzadri·G. Calestani·M. Calicchio·E. Gilioli·F. Bolzoni·R. Cabassi·M. Marezio·A. Migliori
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Abstract

We report on the high pressure synthesis of BiMn$_7$O$_{12}$, a manganite displaying a "quadruple perovskite" structure. Structural characterization of single crystal samples shows a distorted and asymmetrical coordination around the Bi atom, due to presence of the $6s^{2}$ lone pair, resulting in non-centrosymmetric space group Im, leading to a permanent electrical dipole moment and ferroelectric properties. On the other hand, magnetic characterization reveals antiferromagnetic transitions, in agreement with the isostructural compounds, thus evidencing two intrinsic properties that make BiMn$_7$O$_{12}$ a promising multiferroic material.

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F. Mezzadri, G. Calestani, M. Calicchio, E. Gilioli, F. Bolzoni, R. Cabassi, M. Marezio, A. Migliori. 2008-10-03. Synthesis and characterization of multiferroic BiMn$_7$O$_{12}$. https://doi.org/10.1103/physrevb.79.100106

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