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Joint superexchange--Jahn-Teller mechanism for A-type antiferromagnetism in $LaMnO_3$

D. Feinberg·P. Germain·M. Grilli·G. Seibold
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Abstract

We propose a mechanism for A-type antiferromagnetism in orthorombic LaMnO_3, compatible with the large Jahn-Teller splitting inferred from structural data. Orbital ordering resulting from Jahn-Teller distortions effectively leads to A-type ordering (antiferromagnetic in the c axis and ferromagnetic in the ab plane) provided the in-plane distorsion Q_2 is large enough, a condition generally fulfilled in existing data.

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D. Feinberg, P. Germain, M. Grilli, G. Seibold. 1997-10-22. Joint superexchange--Jahn-Teller mechanism for A-type antiferromagnetism in $LaMnO_3$. https://doi.org/10.1103/physrevb.57.r5583

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