Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: First-principles study of the temperature-pressure phase diagram of
  BaTiO3   We investigate the temperature-pressure phase diagram of BaTiO_3 using a
first-principles effective-Hamiltonian approach. We find that the zero-point
motion of the ions affects the form of the phase diagram dramatically.
Specifically, when the zero-point fluctuations are included in the
calculations, all the polar (tetragonal, orthorhombic, and rhombohedral) phases
of BaTiO_3 survive down to 0 K, while only the rhombohedral phase does
otherwise. We provide a simple explanation for this behavior. Our results
confirm the essential correctness of the phase diagram proposed by Ishidate et
al. (Phys. Rev. Lett. 78, 2397 (1997)).

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The categories of this paper are: nucl-th
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The categories of this paper are: q-bio
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The categories of this paper are: stat
27
The categories of this paper are: comp-gas
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The categories of this paper are: math-ph
0
The categories of this paper are: hep-ph
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The categories of this paper are: cs
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The categories of this paper are: econ
22
The categories of this paper are: chao-dyn
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The categories of this paper are: bayes-an
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The categories of this paper are: quant-ph
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The categories of this paper are: funct-an
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The categories of this paper are: physics
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The categories of this paper are: gr-qc
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The categories of this paper are: patt-sol
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The categories of this paper are: nucl-ex