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Temperature excitation of the Co3+ triplet spin-state in LaCoO3 determined by polarized neutron diffraction

V. P. Plakhty·P. J. Brown·B. Grenier·S. V. Shiryaev·S. N. Barilo·S. V. Gavrilov·E. Ressouche
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Abstract

The magnetic moment induced by an external magnetic field of 5.8 T on the Co3+ ions in LaCoO3 has been measured by polarized neutron diffraction. Measurements were made at 100 K, near to the spin-state transition, at 1.5 K and at 285 K. The data give evidence for a transition from the ground singlet state (S = 0) to the excited triplet intermediate spin state (S = 1). The energy of K estimated for the high-spin (S = 2) state, is too high to contribute significantly even at T = 285 K. There is evidence for a small negative covalent spin density associated with the oxygen ligands amounting to about one fifth of the aligned Co3+ moment at all three temperatures.

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V. P. Plakhty, P. J. Brown, B. Grenier, S. V. Shiryaev, S. N. Barilo, S. V. Gavrilov, E. Ressouche. 2005-09-23. Temperature excitation of the Co3+ triplet spin-state in LaCoO3 determined by polarized neutron diffraction. https://doi.org/10.1088/0953-8984%2F18%2F13%2F019

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