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Planar spin exchange in LiNiO_2

A. -M Daré·R. Hayn
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Abstract

We study the planar spin exchange couplings in LiNiO2 using a perturbative approach. We show that the inclusion of the trigonal crystal field splitting at the Oxygen sites leads to the appearance of antiferromagnetic exchange integrals in deviation from the Goodenough-Kanamori-Anderson rules for this 90 degree bond. That gives a microscopic foundation for the recently observed coexistence of ferromagnetic and antiferromagnetic couplings in the orbitally-frustrated state of LiNiO2. (F. Reynaud et al, Phys. Rev. Lett. 86, 3638 (2001))

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A. -M Daré, R. Hayn. 2002-07-03. Planar spin exchange in LiNiO_2. https://doi.org/10.1209/epl%2Fi2003-00305-x

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