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تسجيل مستخدم جديدSynthesis and characterization of multiferroic BiMn$_7$O$_{12}$
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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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