Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: LiFeAs: An Intrinsic FeAs-based Superconductor with Tc = 18K   The synthesis and properties of LiFeAs, a high-Tc Fe-based superconducting
stoichiometric compound, are reported. Single crystal x-ray studies reveal that
it crystallizes in the tetragonal PbFCl type (P4/nmm) with a=3.7914(7) A and
c=6.364(2) A. Unlike the known isoelectronic undoped intrinsic FeAs compounds,
LiFeAs does not show any spin-density wave behavior but exhibits
superconductivity at ambient pressures without chemical doping. It exhibits a
respectable transition temperature of Tc=18 K with electronlike carriers and a
very high critical field, Hc2(0)>80 T. LiFeAs appears to be the chemical
equivalent of the infinite layered compound of the high-Tc cuprates.

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The categories of this paper are: plasm-ph
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The categories of this paper are: physics
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The categories of this paper are: econ
17
The categories of this paper are: q-fin
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The categories of this paper are: atom-ph
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The categories of this paper are: cmp-lg
1
The categories of this paper are: cs
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The categories of this paper are: q-bio
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The categories of this paper are: nlin
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The categories of this paper are: quant-ph
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The categories of this paper are: chem-ph
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The categories of this paper are: math-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: ao-sci
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The categories of this paper are: hep-lat
8
The categories of this paper are: hep-ex