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Thermodynamics of a mixed quantum-classical Heisenberg model in two dimensions

J. Leandri·Y. Leroyer·S. V. Meshkov·Y. Meurdesoif·O. Kahn·B. Mombelli·D. Price
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Abstract

We study the planar antiferromagnetic Heisenberg model on a decorated hexagonal lattice, involving both classical spins (occupying the vertices) and quantum spins (occupying the middle of the links). This study is motivated by the description of a recently synthesized molecular magnetic compound. First, we trace out the spin 1/2 degrees of freedom to obtain a fully classical model with an effective ferromagnetic interaction. Then, using high temperature expansions and Monte Carlo simulations, we analyse its thermal and magnetic properties. We show that it provides a good quantitative description of the magnetic susceptibility of the molecular magnet in its paramagnetic phase.

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J. Leandri, Y. Leroyer, S. V. Meshkov, Y. Meurdesoif, O. Kahn, B. Mombelli, D. Price. 1996-03-14. Thermodynamics of a mixed quantum-classical Heisenberg model in two dimensions. https://doi.org/10.1088/0953-8984%2F8%2F17%2F004

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