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Determination of Exchange Parameters for CaV_4O_9

Ken'ichi Takano·K. Sano
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Abstract

Magnetic susceptibility measured for CaV$_4$O$_9$ is analyzed by a method with high temperature expansion. The analysis is consistent with the $g$-value which is close to 2 and is observed by an ESR experiment. Four exchange parameters in a two-dimensional Heisenberg model are determined to represent CaV$_4$O$_9$. All the exchange parameters are about 500 K and strongly frustrated. The observed spin gap originates from the frustration.

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Ken'ichi Takano, K. Sano. 1996-09-07. Determination of Exchange Parameters for CaV_4O_9. https://arxiv.org/abs/cond-mat/9609073

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