Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Singlet ground state in the spin-1/2 dimer compound Sr3Cr2O8   Magnetic susceptibility and specific heat versus temperature measurements on
polycrystalline samples of Sr3Cr2O8 and the isostructural, nonmagnetic compound
Sr3V2O8 are reported. A Curie-Wiess fit to the high-temperature susceptibility
data for Sr3Cr2O8 indicates that the Cr atoms are in the rare Cr^5+ (Spin S =
1/2) valence state as expected from the composition. The ground state was found
to be a spin singlet with an excitation gap Delta/k_ B = 61.9(1) K to the
magnetic triplet states, and a weak interdimer coupling of 6(2) K was inferred.
The specific heat and susceptibility measurements on Sr3V2O8 reveal a phase
transition at 110 K which is evidently a structural transition.

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The categories of this paper are: comp-gas
3
The categories of this paper are: physics
1
The categories of this paper are: cs
35
The categories of this paper are: mtrl-th
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The categories of this paper are: plasm-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: q-bio
9
The categories of this paper are: nlin
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The categories of this paper are: acc-phys
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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: ao-sci
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The categories of this paper are: quant-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: atom-ph
34
The categories of this paper are: chem-ph