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Charge and orbital order in Fe_3O_4

I. Leonov·A. N. Yaresko·V. N. Antonov·M. A. Korotin·V. I. Anisimov
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Abstract

Charge and orbital ordering in the low-temperature monoclinic structure of magnetite (Fe_3O_4) is investigated using LSDA+U. While the difference between t_{2g} minority occupancies of Fe^{2+}_B and Fe^{3+}_B cations is large and gives direct evidence for charge ordering, the screening is so effective that the total 3d charge disproportion is rather small. The charge order has a pronounced [001] modulation, which is incompatible with the Anderson criterion. The orbital order agrees with the Kugel-Khomskii theory.

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I. Leonov, A. N. Yaresko, V. N. Antonov, M. A. Korotin, V. I. Anisimov. 2004-02-13. Charge and orbital order in Fe_3O_4. https://doi.org/10.1103/physrevlett.93.146404

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