Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: First principles study of magnetism in nanographenes   Magnetism in nanographenes (also know as polycyclic aromatic hydrocarbons, or
PAHs) are studied with first principles density functional calculations. We
find that an antiferromagnetic (AFM) phase appears as the PAH reaches a certain
size. This AFM phase in PAHs has the same origin as the one in infinitely long
zigzag-edged graphene nanoribbons, namely, from the localized electronic state
at the zigzag edge. The smallest PAH still having an AFM ground state is
identified. With increased length of the zigzag edge, PAHs approach an
infinitely long ribbon in terms of (1) the energetic ordering and difference
among the AFM, ferromagnetic (FM), and nonmagnetic (NM) phases and (2) the
average local magnetic moment at the zigzag edges. These PAHs serve as ideal
targets for chemical synthesis of nanographenes that possess magnetic
properties. Moreover, our calculations support the interpretation that
experimentally observed magnetism in activated carbon fibers originates from
the zigzag edges of the nanographenes.

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The categories of this paper are: adap-org
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The categories of this paper are: supr-con
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The categories of this paper are: stat
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The categories of this paper are: math-ph
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The categories of this paper are: quant-ph
0
The categories of this paper are: hep-ph
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The categories of this paper are: econ
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The categories of this paper are: funct-an
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The categories of this paper are: solv-int
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The categories of this paper are: alg-geom
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The categories of this paper are: chem-ph
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The categories of this paper are: cs
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The categories of this paper are: acc-phys
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The categories of this paper are: cond-mat
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The categories of this paper are: eess
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The categories of this paper are: q-bio