Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: First-Principles investigation of the First-order Phase Transition in
  Kagome Na$_2$Ti$_3$Cl$_8$   The antiferromagnetic kagome material Na2Ti3Cl8 exhibits a first-order phase
transition; the low-temperature phase is characterized by the trimerizations of
Ti ions. In this work, we carry out first-principles calculations on the
crystal and electronic structure of Na$_2$Ti$_3$Cl$_8$ at the high- and
low-temperature phases. The crystal structures, including the lattice constant
and the trimerization of Ti ions, are well reproduced by taking account a small
Hubbard correction of 1 eV. The calculated total energy landscape reveals a
first-order phase transition with the total energy barrier of 80 meV per
formula unit. Analysis of the electronic structure indicates a direct metal
bonding among Ti in the trimierized low-temperature phase.

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The categories of this paper are: math-ph
9
The categories of this paper are: nlin
28
The categories of this paper are: alg-geom
22
The categories of this paper are: chao-dyn
31
The categories of this paper are: ao-sci
2
The categories of this paper are: math
32
The categories of this paper are: atom-ph
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The categories of this paper are: quant-ph
3
The categories of this paper are: physics
29
The categories of this paper are: funct-an
37
The categories of this paper are: supr-con
6
The categories of this paper are: astro-ph
18
The categories of this paper are: econ
26
The categories of this paper are: bayes-an
7
The categories of this paper are: hep-th
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The categories of this paper are: hep-lat