Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Designing rigid carbon foams   We use ab initio density functional calculations to study the stability,
elastic properties and electronic structure of sp2 carbon minimal surfaces with
negative Gaussian curvature, called schwarzites. We focus on two systems with
cubic unit cells containing 152 and 200 carbon atoms, which are metallic and
very rigid. The porous schwarzite structure allows for efficient and reversible
doping by electron donors and acceptors, making it a promising candidate for
the next generation of alkali ion batteries. We identify schwarzite structures
that act as arrays of interconnected quantum spin dots or become magnetic when
doped. We introduce two interpenetrating schwarzite structures that may find
their use as the ultimate super-capacitor.

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The categories of this paper are: patt-sol
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The categories of this paper are: q-alg
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The categories of this paper are: dg-ga
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The categories of this paper are: physics
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The categories of this paper are: chem-ph
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The categories of this paper are: solv-int
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The categories of this paper are: q-bio
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The categories of this paper are: funct-an
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The categories of this paper are: econ
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The categories of this paper are: cs
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The categories of this paper are: astro-ph
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The categories of this paper are: ao-sci
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The categories of this paper are: eess
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The categories of this paper are: chao-dyn
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The categories of this paper are: adap-org
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The categories of this paper are: mtrl-th