Nature and extent of melting in superheated solids: Liquid-solid coexistence model

The nature and extent of superheating in solids have remained an open problem for nearly a century. Using a liquid-solid coexistence model, we critically examined melting in the superheating regime. It is found that the solid/liquid density difference and the interface disordering at melting are two key factors determining the nature of the transition and the extent of superheating. A nucleation forbidden gap is found due to the density difference. The nucleation barrier rising from the interface is reduced by the interface disordering. The results obtained from the theoretical model are in excellent agreement with those in atomistic simulations.