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arXiv · 2501.04414

Double perovskite Ba2NaOsO6: Magnetic structure, Kramers doublet and x-ray magnetic dichroic signals

S W Lovesey
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Abstract

Of all the oxides of osmium, Ba2NaOsO6 is the only one with a substantial ferromagnetic moment. A fresh theoretical study of bulk magnetic properties of the double perovskite is accomplished with an appropriate space group, and an atomic model of a Kramers doublet formed by the single osmium d-electron. It possesses symmetry demanded by the Wyckoff position assigned to Os in a canted ferromagnet. Whereupon, magnetic moments in the paramagnetic and magnetically ordered states of Ba2NaOsO6 are unified. Analytic x-ray magnetic dichroic signals (XMCD) at osmium L2 and L3 absorption edges are presented, and shown to agree with hitherto unexplained recent measurements.

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S W Lovesey. 2025-01-08. Double perovskite Ba2NaOsO6: Magnetic structure, Kramers doublet and x-ray magnetic dichroic signals. https://arxiv.org/abs/2501.04414

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