Molecular-dynamics study of a phase transition in a system of interacting anharmonic oscillators

The molecular-dynamics tenchnique is applied to the study of a classical system of anharmonic oscillators interacting via a nearest-neighbor coupling plus a coupling which is infinitely long range in character. Such a system undergoes a second-order phase transition at a finite temperature which depends upon the strength of the long-range coupling. The overall features of the transition are seen to be fairly well described by the self-consistent phonon approximation and evidence is found that the system as a whole fluctuates between a displaced and an undisplaced phase in the vicinity of the transition. © The American Physical Society.