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Crystal and magnetic structure of LaTiO3 : evidence for non-degenerate $t_{2g}$-orbitals

M. Cwik·T. Lorenz·J. Baier·R. Mueller·G. Andre·F. Bouree·F. Lichtenberg·A. Freimuth·E. Mueller-Hartmann·M. Braden
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Abstract

The crystal and magnetic structure of LaTiO3 ~ has been studied by x-ray and neutron diffraction techniques using nearly stoichiometric samples. We find a strong structural anomaly near the antiferromagnetic ordering, T$_N$=146 K. In addition, the octahedra in LaTiO3 exhibit an intrinsic distortion which implies a splitting of the t2g-levels. Our results indicate that LaTiO3 should be considered as a Jahn-Teller system where the structural distortion and the resulting level splitting are enhanced by the magnetic ordering.

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M. Cwik, T. Lorenz, J. Baier, R. Mueller, G. Andre, F. Bouree, F. Lichtenberg, A. Freimuth, E. Mueller-Hartmann, M. Braden. 2003-08-08. Crystal and magnetic structure of LaTiO3 : evidence for non-degenerate $t_{2g}$-orbitals. https://doi.org/10.1103/physrevb.68.060401

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