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Charge order in Fe2OBO3: An LSDA+U study

I. Leonov·A. N. Yaresko·V. N. Antonov·J. P. Attfield·V. I. Anisimov
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Abstract

Charge ordering in the low-temperature monoclinic structure of iron oxoborate (Fe2OBO3) is investigated using the local spin density approximation (LSDA)+U method. While the difference between t_{2g} minority occupancies of Fe^{2+} and Fe^{3+} cations is large and gives direct evidence for charge ordering, the static "screening" is so effective that the total 3d charge separation is rather small. The occupied Fe^{2+} and Fe^{3+} cations are ordered alternately within the chain which is infinite along the a-direction. The charge order obtained by LSDA+U is consistent with observed enlargement of the βangle. An analysis of the exchange interaction parameters demonstrates the predominance of the interribbon exchange interactions which determine the whole L-type ferrimagnetic spin structure.

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I. Leonov, A. N. Yaresko, V. N. Antonov, J. P. Attfield, V. I. Anisimov. 2005-02-23. Charge order in Fe2OBO3: An LSDA+U study. https://doi.org/10.1103/physrevb.72.014407

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