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Determination of the exchange energies in Li2VOSiO4 from a high-temperature series analysis of the square lattice J1-J2 Heisenberg model

G. Misguich·B. Bernu·L. Pierre
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Abstract

We present a high-temperature expansion (HTE) of the magnetic susceptibility and specific heat data of Melzi et al. on Li2VOSiO4 [Phys. Rev. B 64, 024409 (2001)]. The data are very well reproduced by the J1-J2 Heisenberg model on the square lattice with exchange energies J1=1.25+-0.5 K and J2=5.95+-0.2 K. The maximum of the specific heat Cv^{max}(T_{max}) is obtained as a function J2/J1 from an improved method based on HTE.

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G. Misguich, B. Bernu, L. Pierre. 2003-02-27. Determination of the exchange energies in Li2VOSiO4 from a high-temperature series analysis of the square lattice J1-J2 Heisenberg model. https://doi.org/10.1103/physrevb.68.113409

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