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Magnetic Structure and dielectric properties of antiferromagnetic FeCrO3

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 نشر من قبل A. Venimadhav
 تاريخ النشر 2019
  مجال البحث فيزياء
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We report the enhancement of Neel temperature of Cr2O3 by replacing 50% of Cr by Fe prepared by sol-gel method. The structural analysis by neutron diffraction has revealed that FeCrO3 belongs to a corundum structure (R-3c space group) with an antiferromagnetic spin structure having collinear spins along a-axis with propagation vector k=0; the high-temperature magnetisation study indicated a Neel temperature of 560 K. The enhancement in Neel temperature has been attributed to the strong orbital hybridization that leads to change in nearest neighbor bond angle and bond distances. Impedance spectroscopy has revealed conduction mechanism at low temperature is due to the polaron hopping while extrinsic contributions from the Maxwell-Wagner dominant at high temperatures

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