On the Temperature‐ and Pressure‐Dependent Structure of Liquid Phosphorus: A Reverse Monte Carlo Study

Abstract

Apart from the well-known molten white phosphorus, existing at temperatures around 50 °C under atmospheric pressure, early in this millennium, new high-pressure, high-temperature phases have been discovered. One group of the newly found liquids can be identified as being formed by P4 molecules, just like common molten white phosphorus. The structures of these (“old” and “new”) forms have not yet been compared in detail: this comparison is in the focus of the present work. Orientational correlations between P4 tetrahedra, as a function of the distance between centers of tetrahedra, have been revealed. It is found that face-to-face type contacts occur at much lower center–center distances in the newly discovered liquids. As an addition, new estimates, based on series of Reverse Monte Carlo calculations, for the densities of the high-temperature phases are provided; this step is necessary because in this respect, sizeable uncertainties have been reported previously.