Structural Aspects of Magnetic Coupling in CaV4O9

W. E. Pickett

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Structural Aspects of Magnetic Coupling in CaV4O9

W. E. Pickett

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Abstract

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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W. E. Pickett. 1997-04-24. Structural Aspects of Magnetic Coupling in CaV4O9. https://arxiv.org/abs/cond-mat/9704203

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