Pressure and Temperature Induced Liquid-Liquid Phase Transition of Phosphorus

Abstract

We report constant-pressure first-principles molecular-dynamics simulations on liquid-liquid phase transition of phosphorus. By compressing a low-pressure liquid composed of tetrahedral P₄ molecules, a structural transition from a molecular to polymeric liquid (a high-pressure liquid) observed in the recent experiment by Katayama et al. [Nature 403, 170 (2000)] was successfully realized. It is found that this transition is caused by a breakup of the tetrahedral molecules with large volume contraction. The same transition is also realized by heating. This indicates that only the polymeric liquid can stably exist at high temperatures.