On the deviation from a Curie-Weiss behavior of the ZnFe 2 O 4 susceptibility: A combined ab-initio and Monte-Carlo approach.

We present a numerical study of the magnetic properties of ZnFe2 O4 using Monte-Carlo simulations performed considering a Heisenberg model with antiferromagnetic couplings determined by Density Functional Theory. Our calculations predict that the magnetic susceptibility has a cusp-like peak centered at 13 K, and follows a Curie-Weiss behavior above this temperature with a high and negative Curie-Weiss temperature ( Θ C W = - 170 K). These results agree with the experimental data once extrinsic contributions that give rise to the deviation from a Curie-Weiss law are discounted. Additionally, we discuss the spin configuration of ZnFe2 O4 below its ordering temperature, where the system presents a high degeneracy.