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Lattice Distortion and Magnetic Ground State of YTiO$_3$ and LaTiO$_3$

I. V. Solovyev
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Abstract

Effects of lattice distortion on the magnetic ground state of YTiO$_3$ and LaiO$_3$ are investigated on the basis accurate tight-binding parametrization of the $t_{2g}$ electronic structure extracted from the local-density approximation. The complexity of these compounds is related with the fact that the $t_{2g}$-level splitting, caused by lattice distortions, is comparable with the energies of superexchange and spin-orbit interactions. Therefore, all these interactions are equally important and should be treated on an equal footing. The Hartree-Fock approximation fails to provide a coherent description simultaneously for YTiO$_3$ and LaTiO$_3$, and it is essential to go beyond.

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I. V. Solovyev. 2003-10-24. Lattice Distortion and Magnetic Ground State of YTiO$_3$ and LaTiO$_3$. https://doi.org/10.1103/physrevb.69.134403

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