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Influence of the lattice geometry on the thermodynamical properties of two-dimensional spin systems

B. Mombelli·O. Kahn·J. Leandri·Y. Leroyer·S. Mechkov·Y. Meurdesoif
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Abstract

Various types of mixed spin two-dimensional Heisenberg networks are investigated by means of Monte Carlo simulations. This study aims at interpreting quantitatively the thermodynamical properties of two-dimensional molecule-based magnets recently synthesized. The proposed model requires that: (i) one of the two magnetic centers has a spin large enough to be treated as a classical spin; (ii) the zero field Hamiltonian is isotropic; (iii) the quantum spins have only classical spins as neighbours. The quantum Hamiltonian is then replaced by a classical one with effective ferromagnetic interactions. The temperature dependence of both the specific heat and magnetic susceptibility are calculated. The effect of the lattice geometry is analysed.

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B. Mombelli, O. Kahn, J. Leandri, Y. Leroyer, S. Mechkov, Y. Meurdesoif. 1997-10-18. Influence of the lattice geometry on the thermodynamical properties of two-dimensional spin systems. https://doi.org/10.1088/0953-8984%2F10%2F23%2F019

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