Phase Diagram for a Lennard-Jones System Obtained through Constant-Pressure Molecular Dynamics Simulations

Abstract

the phase diagram for a Lennard-Jones system was estimated using conventional NPH molecular dynamics (md) simulations. Standard periodic boundaries were assumed for unit cells containing 1000 molecules. an elongated unit cell with both solid and vacuum sections was found to be suitable for the NPH md simulations when calculating both the melting and vapor pressure curves under pressures lower than the critical one. Under high pressures, a unit cell with both solid and liquid sections was used as the initial configuration to obtain the melting temperature. The results of these simulations were compared with the phase transition point given by the reported equations of state.