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arXiv · 2204.09856

Magnetic Couplings in Edge-Sharing High-Spin $d^7$ Compounds

Stephen M. Winter
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Abstract

High-spin $d^7$ Co(II) compounds have recently been identified as possible platforms for realising highly anisotropic and bond-dependent couplings featured in quantum-compass models such as the celebrated Kitaev model. In order to evaluate this potential, we consider all symmetry-allowed contributions to the magnetic exchange for ideal edge-sharing bonds. Though a combination of ab-initio and cluster many-body calculations we conclude that bond-dependent couplings are generally suppressed in favor of Heisenberg exchange for real materials. Consequences for several prominent materials including Na$_2$Co$_2$TeO$_6$ and BaCo$_2$(AsO$_4$)$_2$ are discussed.

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Stephen M. Winter. 2022-04-21. Magnetic Couplings in Edge-Sharing High-Spin $d^7$ Compounds. https://doi.org/10.1088/2515-7639%2Fac94f8

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