The melting line of diamond determined via atomistic computer simulations

The diamond melting line was determined for a model system based on Brenner 's bond order potential for hydrocarbon systems. The location of this first -order phase boundary was found by a free energy calculation of the diamond and liquid phases, using atomistic simulation methods. The melting line wa s found to have a positive slope consistent with the present understanding. The location at lower pressure was also consistent with experiment and a n umber of other theoretical approaches. The slope is found to increase with pressure. The structure of the liquid is examined as a function of density and is suggestive of a Liquid-liquid phase boundary. (C) 1999 American Inst itute of Physics. [S0021-9606(99)51201-4].