Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Structural stability of CuAl$_{2}$O$_{4}$ under pressure   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.

29
The categories of this paper are: funct-an
16
The categories of this paper are: stat
24
The categories of this paper are: dg-ga
31
The categories of this paper are: ao-sci
19
The categories of this paper are: eess
5
The categories of this paper are: gr-qc
34
The categories of this paper are: chem-ph
13
The categories of this paper are: quant-ph
14
The categories of this paper are: math-ph
15
The categories of this paper are: nucl-ex
2
The categories of this paper are: math
8
The categories of this paper are: hep-ex
10
The categories of this paper are: q-bio
27
The categories of this paper are: comp-gas
3
The categories of this paper are: physics
35
The categories of this paper are: mtrl-th