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Evidence for orbital ordering in LaCoO3

G. Maris·Y. Ren·V. Volotchaev·C. Zobel·T. Lorenz·T. T. M. Palstra
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Abstract

We present powder and single crystal X-ray diffraction data as evidence for a monoclinic distortion in the low spin (S=0) and intermediate spin state (S=1) of LaCoO3. The alternation of short and long bonds in the ab plane indicates the presence of eg orbital ordering induced by a cooperative Jahn-Teller distortion. We observe an increase of the Jahn-Teller distortion with temperature in agreement with a thermally activated behavior of the Co3+ ions from a low-spin ground state to an intermediate-spin excited state.

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G. Maris, Y. Ren, V. Volotchaev, C. Zobel, T. Lorenz, T. T. M. Palstra. 2003-04-29. Evidence for orbital ordering in LaCoO3. https://doi.org/10.1103/physrevb.67.224423

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