Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Centers of near-infrared luminescence in bismuth-doped TlCl and CsI
  crystals   A comparative first-principles study of possible bismuth-related centers in
TlCl and CsI crystals is performed and the results of computer modeling are
compared with the experimental data. The calculated spectral properties of the
bismuth centers suggest that the IR luminescence observed in TlCl:Bi is most
likely caused by Bi--Vac(Cl) centers (Bi^+ ion in thallium site and a
negatively charged chlorine vacancy in the nearest anion site). On the
contrary, Bi^+ substitutional ions and Bi_2^+ dimers are most likely
responsible for the IR luminescence observed in CsI:Bi.

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The categories of this paper are: quant-ph
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The categories of this paper are: astro-ph
17
The categories of this paper are: q-fin
5
The categories of this paper are: gr-qc
20
The categories of this paper are: acc-phys
34
The categories of this paper are: chem-ph
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The categories of this paper are: dg-ga
16
The categories of this paper are: stat
0
The categories of this paper are: hep-ph
2
The categories of this paper are: math
23
The categories of this paper are: solv-int
11
The categories of this paper are: hep-lat
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The categories of this paper are: q-bio
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The categories of this paper are: hep-ex
1
The categories of this paper are: cs
29
The categories of this paper are: funct-an