Two-level Ising-like model for spin-crossover phenomenon including the magnetic field effect:: the mean-field approximation and Monte Carlo resolutions

In this paper we analysed the magnetic field effect on the spin-crossover phenomenon using different theoretical approaches: thermodynamic and Ising-like models. This latter, including magnetic field, was treated in the mean-field approximation and-for the first time-by Monte Carlo numerical method. We propose an adaptation of the metropolis algorithm to take into account the different degeneracies of the high and low-spin levels and their Zeeman splitings due to the effect of magnetic field in both states. A comparison of both methods is given and discussed. (C) 2003 Elsevier Science Ltd. All rights reserved.