Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The chemical physics of unconventional superconductivity   Attempts to explain correlated-electron superconductivity have largely
focused on the proximity of the superconducting state to antiferromagnetism.
Yet, there exist many correlated-electron systems that exhibit
insulator-superconducting transitions where the insulating state exhibits
spatial broken symmetry different from antiferromagnetism. Here we focus on a
subset of such compounds which are seemingly very different in which specific
chemical stoichiometries play a distinct role, and small deviations from
stoichiometry can destroy superconductivity. These superconducting materials
share a unique carrier concentration, at which we show there is a stronger than
usual tendency to form local spin-singlets. We posit that superconductivity is
a consequence of these pseudomolecules becoming mobile as was suggested by
Schafroth a few years prior to the advent of the BCS theory.

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The categories of this paper are: patt-sol
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The categories of this paper are: hep-lat
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The categories of this paper are: alg-geom
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The categories of this paper are: atom-ph
30
The categories of this paper are: q-alg
2
The categories of this paper are: math
34
The categories of this paper are: chem-ph
1
The categories of this paper are: cs
18
The categories of this paper are: econ
9
The categories of this paper are: nlin
14
The categories of this paper are: math-ph
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The categories of this paper are: eess
5
The categories of this paper are: gr-qc
22
The categories of this paper are: chao-dyn
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The categories of this paper are: astro-ph
33
The categories of this paper are: plasm-ph