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Spin Gap of S=1/2 Heisenberg Model on Distorted Diamond Chain

Kazuhiro Sano·Ken'ichi Takano
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Abstract

We study the spin gap of the S=1/2 Heisenberg model on the distorted diamond chain, which is recently proposed to represent magnetic properties of Cu_3 Cl_6 (H_2 O)_2 2H_8 C_4 SO_2. This model is composed of stacked trimers and has three kinds of exchange interactions J_1, J_2 and J_3. Using the numerical diagonalization, we obtain a contour map of the spin gap in the J_2/J_1-J_3/J_1 plane. We argue possible values of the exchange constants based on the contour map and the observed value of the spin gap.

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Kazuhiro Sano, Ken'ichi Takano. 2000-05-17. Spin Gap of S=1/2 Heisenberg Model on Distorted Diamond Chain. https://doi.org/10.1143/jpsj.69.2710

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