Melting and critical superheating

Two mechanisms of melting are known, heterogeneous, where melting starts at surfaces, and homogeneous, where the liquid nucleates in the bulk crystal. If melting occurs homogeneously, a crystal can be superheated significantly above its melting temperature (Tₘ). At present, the physical meaning of the limit of superheating (TLS) is unknown. We demonstrate, by molecular dynamics simulations, that the total energy of a solid at TLS is equal to the total energy of its liquid at Tₘ at the same volume. In the high pressure limit TLS and Tₘ are connected by the constant kAB=ln0.2em0ex2∕3 via the relation kAB=TLS∕Tₘ-1.