Effect of magnetoelastic interactions on the phase transition of two-dimensional Ising spin system

Using Monte Carlo simulations, we study a two-dimensional (2D) system of pa rticles interacting with each other through short-range cohesive and magnet ic interactions, using the Lennard-Jones potential. The spin on each partic le is of Ising type. Results obtained depend on the ratio Q between the coh esive and magnetic interaction strengths. For strong cohesive interaction, with Q > 1.55, the magnetic phase transition remains that of the 2D Ising u niversality class. For 1 < Q < 1.55, the phase transition becomes first ord er. (C) 2000 American Institute of Physics. [S0021-8979(00)94708-X].