Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Structural Aspects of Magnetic Coupling in CaV4O9   The strong corrugation of the V4O9 layer in the spin gap system CaV4O9 is
examined for its impact on the exchange coupling constants between the spin 1/2
V ions. Local spin density (LSD) calculations show that the V spin occupies a
d(x^2-y^2) orbital (x and y are the V-V directions). The Kanamori-Goodenough
superexchange rules, and the degeneracy of ferromagnetic and antiferromagnetic
alignments within LSD, suggest that 2nd neighbor couplings dominate over
nearest neighbor, resulting in two coupled S=1/2 metaplaquette systems.

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The categories of this paper are: acc-phys
0
The categories of this paper are: hep-ph
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The categories of this paper are: dg-ga
2
The categories of this paper are: math
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The categories of this paper are: quant-ph
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The categories of this paper are: chem-ph
7
The categories of this paper are: hep-th
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The categories of this paper are: solv-int
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The categories of this paper are: q-fin
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The categories of this paper are: adap-org
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The categories of this paper are: mtrl-th
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The categories of this paper are: ao-sci
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The categories of this paper are: gr-qc
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The categories of this paper are: comp-gas
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The categories of this paper are: chao-dyn
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The categories of this paper are: cs