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Spin Susceptibility and Superexchange Interaction in the Antiferromagnet CuO

T. Shimizu·T. Matsumoto·A. Goto·T. V. Chandrasekhar Rao·K. Yoshimura·K. Kosuge
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Abstract

Evidence for the quasi one-dimensional (1D) antiferromagnetism of CuO is presented in a framework of Heisenberg model. We have obtained an experimental absolute value of the paramagnetic spin susceptibility of CuO by subtracting the orbital susceptibility separately from the total susceptibility through the $^{63}$Cu NMR shift measurement, and compared directly with the theoretical predictions. The result is best described by a 1D $S=1/2$ antiferromagnetic Heisenberg (AFH) model, supporting the speculation invoked by earlier authors. We also present a semi-quantitative reason why CuO, seemingly of 3D structure, is unexpectedly a quasi 1D antiferromagnet.

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T. Shimizu, T. Matsumoto, A. Goto, T. V. Chandrasekhar Rao, K. Yoshimura, K. Kosuge. 2003-05-02. Spin Susceptibility and Superexchange Interaction in the Antiferromagnet CuO. https://doi.org/10.1103/physrevb.68.224433

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