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Pressure-driven orbital reorientation and change in Mott-Hubbard gap in YTiO3

I. Loa·X. Wang·K. Syassen·H. Roth·T. Lorenz·M. Hanfland·Y. -L. Mathis
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Abstract

We investigate the crystal structure of YTiO3 at high pressures up to 30 GPa by synchrotron x-ray powder diffraction (T = 295 K). The variation of the Ti--O bond lengths with pressure evidences a distinct change in the distortion of the TiO_6 octahedra at around 10 GPa, indicating a pressure-driven spatial reorientation of the occupied Ti 3d(t_2g) orbitals. The pressure-induced reduction of the optical band gap of YTiO3 is determined quantitatively by mid-infrared synchrotron micro-spectroscopy and discussed in terms of bond length and orbital orientation changes.

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I. Loa, X. Wang, K. Syassen, H. Roth, T. Lorenz, M. Hanfland, Y. -L. Mathis. 2005-04-15. Pressure-driven orbital reorientation and change in Mott-Hubbard gap in YTiO3. https://doi.org/10.1088/0953-8984%2F19%2F40%2F406223

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