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arXiv · 1105.1276

Structural investigation of LaAlO3 up to 63 GPa

Mael Guennou·Pierre Bouvier·Gaston Garbarino·Jens Kreisel
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Abstract

We report a high-pressure single-crystal synchrotron x-ray diffraction on a LaAlO3 single crystal. The transition from rhombohedral to cubic at 14.8 GPa is confirmed by the loss of the superstructure reflections, whose intensity shows a linear pressure dependence, characteristic of a second-order transition. The crystal remains cubic up to 63 GPa, the highest pressure reached, which provides a confirmation over a very large pressure range of the general rules for the evolution of distortions of perovskites under pressure. We give the parameters of Birch-Murnaghan equations of state in the low- and high-pressure phases and discuss the evolution of the bulk modulus.

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Mael Guennou, Pierre Bouvier, Gaston Garbarino, Jens Kreisel. 2011-07-02. Structural investigation of LaAlO3 up to 63 GPa. https://doi.org/10.1088/0953-8984%2F23%2F39%2F395401

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