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Crystal structure of LaTiO_3.41 under pressure

I. Loa·K. Syassen·X. Wang·F. Lichtenberg·M. Hanfland·C. A. Kuntscher
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Abstract

The crystal structure of the layered, perovskite-related LaTiO_3.41 (La_5Ti_5O_{17+δ}) has been studied by synchrotron powder x-ray diffraction under hydrostatic pressure up to 27 GPa (T = 295 K). The ambient-pressure phase was found to remain stable up to 18 GPa. A sluggish, but reversible phase transition occurs in the range 18--24 GPa. The structural changes of the low-pressure phase are characterized by a pronounced anisotropy in the axis compressibilities, which are at a ratio of approximately 1:2:3 for the a, b, and c axes. Possible effects of pressure on the electronic properties of LaTiO_3.41 are discussed.

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I. Loa, K. Syassen, X. Wang, F. Lichtenberg, M. Hanfland, C. A. Kuntscher. 2004-02-27. Crystal structure of LaTiO_3.41 under pressure. https://doi.org/10.1103/physrevb.69.224105

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