Investigation of the effect of the off-diagonal Onsager rate coefficient on the relaxation dynamics of anhydrous dihalides of iron-group elements

The effect of the off-diagonal Onsager rate coefficient on the relaxation process of iron-group dihalides has been investigated within the framework of statistical equilibrium theory and the thermodynamics of irreversible processes. For this purpose linearized kinetic equations of the total and staggered magnetization is utilized to study the effect of the off-diagonal kinetic coefficient γ on the temperature dependence of the relaxation times near the first order, critical and multicritical points of the spin-12 metamagnetic Ising model. In accordance with the previous results in the literature, we have observed a non-critical maxima of one the relaxation times below the critical temperature according to the values of off-diagonal coefficient.