Studies in molecular dynamics. XVIII. The square-well phase diagram

Accurate molecular dynamics calculations have been made for the thermodynamic properties of the square-well potential in the solid phase. Hard-sphere perturbation terms for fcc and hcp phases have been computed over the solid range, and a phase diagram including solid–solid and solid–liquid phase boundaries has been constructed. The discontinuous square-well potential gives rise to an fcc–fcc phase transition which ends in a critical point. Both fcc and hcp phases have regions of stability, but calculations show that bcc is unstable.