Characterization of the reorientation transition in classical Heisenberg models with dipole interaction

In this paper the thermodynamics of thin ferromagnetic films are studied in the framework of the classical Heisenberg model with uniaxial anisotropy and long-range dipole interaction. The dependence of the order of the reorientation transition in these systems on the number of layers and on the distribution of anisotropies is investigated using both mean field theory and Monte-Carlo simulations.