Solid-solid and liquid-solid phase equilibria for the restricted primitive model

A Monte Carlo simulation study is made of the phase diagram of the restricted primitive model and of the solid-liquid and solid-solid phase coexistence curves in particular. At low temperatures, there is liquid-bcc coexistence and with increasing density there is bcc-fcc coexistence. These coexistence curves end in a triple point (liquid-bcc-fcc) above which only liquid-fcc coexistence is observed.