Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: First-principles study of optical, elastic anisotropic and thermodynamic
  properties of TiN under high temperature and high pressure   The optical, elastic anisotropic and thermodynamic properties of TiN in the
NaCl (B1) structure are analyzed in detail in the temperature range from 0 to
2000 K and the pressure range from 0 to 20 GPa. From the calculated dielectric
constants, a first order isostructural phase transition between 29 and 30 GPa
is found for TiN. The absorption spectra exhibit high values ranging from the
far infrared region to the ultra-violet one. The anisotropy value of Young's
modulus of TiN is smaller than that of c-BN at 0 GPa and the anisotropy of TiN
clearly increases with an increase of pressure. The effects of pressure and
temperature on the bulk modulus, Gr\"uneisen parameter, Gibbs free energy, and
Debye temperature are significant. The Gr\"uneisen parameter of TiN is much
larger than that of c-BN. At temperatures below 1000 K, TiN's heat capacity is
much larger than that of c-BN.

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The categories of this paper are: dg-ga
18
The categories of this paper are: econ
16
The categories of this paper are: stat
13
The categories of this paper are: quant-ph
21
The categories of this paper are: adap-org
26
The categories of this paper are: bayes-an
34
The categories of this paper are: chem-ph
32
The categories of this paper are: atom-ph
14
The categories of this paper are: math-ph
7
The categories of this paper are: hep-th
36
The categories of this paper are: cmp-lg
19
The categories of this paper are: eess
2
The categories of this paper are: math
6
The categories of this paper are: astro-ph
8
The categories of this paper are: hep-ex
37
The categories of this paper are: supr-con