Thermal hysteresis loops in spin-crossover compounds analyzed in terms of classical Preisach model

We apply the classical Preisach model to reproduce the major and minor thermal hysteresis loops in the high-spin <-> low-spin transition for [Fe(btr)(2)(NCS)(2)]H2O and Fe(bt)(2)(NCS)(2) (bt = 2,2'-bi-thiazoline). For this purpose, we consider that spin transition occurs through spin domains which are characterized by the up and down switching temperatures T-alpha and T-beta of a square-shaped thermal hysteresis loop. For each compound, we determine a Gaussian Preisach distribution P(T-alpha,T-beta) which fits the experimental data.