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Orbital frustration at the origin of the magnetic behavior in LiNiO2

F. Reynaud·D. Mertz·F. Celestini·J. -M. Debierre·A. M. Ghorayeb·P. Simon·A. Stepanov·J. Voiron·C. Delmas
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Abstract

We report on the ESR, magnetization and magnetic susceptibility measurements performed over a large temperature range, from 1.5 to 750 K, on high-quality stoichiometric LiNiO2. We find that this compound displays two distinct temperature regions where its magnetic behavior is anomalous. With the help of a statistical model based on the Kugel'-Khomskii Hamiltonian, we show that below T_of ~ 400 K, an orbitally-frustrated state characteristic of the triangular lattice is established. This then gives a solution to the long-standing controversial problem of the magnetic behavior in LiNiO2.

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F. Reynaud, D. Mertz, F. Celestini, J. -M. Debierre, A. M. Ghorayeb, P. Simon, A. Stepanov, J. Voiron, C. Delmas. 2001-02-27. Orbital frustration at the origin of the magnetic behavior in LiNiO2. https://doi.org/10.1103/physrevlett.86.3638

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