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arXiv · 1910.10530

Mechanism of ferromagnetic ordering of the Mn chains in CaMnGe$_2$O$_6$ clinopyroxene

F. V. Temnikov·E. V. Komleva·Z. V. Pchelkina·S. V. Streltsov
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Abstract

The electronic and magnetic properties of clinopyroxene CaMnGe$_2$O$_6$ were studied using density function calculations within the GGA+U approximation. It is shown that anomalous ferromagnetic ordering of neighboring chains is due to a "common-enemy" mechanism. Two antiferromagnetic exchange couplings between nearest neighbours within the Mn-Mn chain and interchain coupling via two GeO$_4$ tetrahedra suppress antiferromagnetic exchange via single GeO$_4$ tetrahedron and stabilize ferromagnetic ordering of Mn chains.

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F. V. Temnikov, E. V. Komleva, Z. V. Pchelkina, S. V. Streltsov. 2019-10-23. Mechanism of ferromagnetic ordering of the Mn chains in CaMnGe$_2$O$_6$ clinopyroxene. https://doi.org/10.1134/s0021364019210033

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