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arXiv · 1405.2730

Jahn-Teller distortions and charge, orbital and magnetic orders in NaMn7O12

S. V. Streltsov·D. I. Khomskii
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Abstract

With the use of the band structure calculations we demonstrate that previously reported [Nat. Materials {\bf 3}, 48 (2004)] experimental crystal and magnetic structures for NaMn$_7$O$_{12}$ are inconsistent with each other. The optimization of the crystal lattice allows us to predict a new crystal structure for the low temperature phase, which is qualitatively different from the one presented before. The AFM-CE type of the magnetic order stabilizes the structure with the elongated, not compressed Mn$^{3+}_B$O$_6$ octahedra, striking NaMn$_7$O$_{12}$ out of the list of the anomalous Jahn-Teller systems. The orbital correlations were shown to exist even in the cubic phase, while the charge order appears only in the low temperature distorted phase.

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S. V. Streltsov, D. I. Khomskii. 2014-05-12. Jahn-Teller distortions and charge, orbital and magnetic orders in NaMn7O12. https://doi.org/10.1103/physrevb.89.201115

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