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arXiv · 2010.02640

Structural stability of CuAl$_{2}$O$_{4}$ under pressure

P. A. Agzamova·A. A. Belik·S. V. Streltsov
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Abstract

Structural properties of CuAl$_{2}$O$_{4}$, which was recently argued to show unusual suppression of the Jahn-Teller distortions by the spin-orbit coupling, are investigated under pressures up to 6 GPa. Analysis of X-ray powder diffraction experiments shows that CuAl$_{2}$O$_{4}$ gets unstable and decomposes onto CuO and Al$_{2}$O$_{3}$ at pressures $\sim$ 6 GPa and temperature $\sim$ 1000 K. This finding is complemented by the DFT+U+SOC calculations, which demonstrate that this instability is partially driven by a (relatively) large compressibility of strongly Jahn-Teller distorted CuO.

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P. A. Agzamova, A. A. Belik, S. V. Streltsov. 2020-10-06. Structural stability of CuAl$_{2}$O$_{4}$ under pressure. https://doi.org/10.1088/1361-648x/abba68

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