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arXiv · 2301.09343

Charge localization, frustration relief, and spin-orbit coupling in U$_3$O$_8$

Rolando Saniz·Gianguido Baldinozzi·Ine Arts·Gregory Leinders·Dirk Lamoen·Marc Verwerft
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Abstract

Research efforts on the low temperature magnetic order and electronic properties of U$_3$O$_8$ have been inconclusive so far. Reinterpreting neutron scattering results, we use group representation theory to show that the ground state presents collinear out-of-plane magnetic moments, with antiferromagnetic coupling both in-layer and between layers. Charge localization relieves the initial geometric frustration, generating a slightly distorted honeycomb sublattice with N\'eel order. We show, furthermore, that spin-orbit coupling has a giant effect on the conduction band states and band gap value. Our results allow a reinterpretation of recent optical absorption measurements.

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Rolando Saniz, Gianguido Baldinozzi, Ine Arts, Gregory Leinders, Dirk Lamoen, Marc Verwerft. 2023-01-23. Charge localization, frustration relief, and spin-orbit coupling in U$_3$O$_8$. https://arxiv.org/abs/2301.09343

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