Crystal-melt and melt-vapor interfaces of nickel

The equilibrium crystal-to-melt interfaces for Ni(001) and Ni(111) and themelt-to-vapor interface are investigated at the melting point, with use ofmolecular-dynamics simulations and the embedded-atom method. The meltingtemperature of nickel determined from these simulations is1733+-22 K, in good agreement with the experimental value.The crystal-to-melt interface is found to be characterized by liquid layering,with properties such as structural order parameters and diffusion coefficientsvarying gradually across the transition region. The transition region extendsover several layers and is more diffuse at the (001) interface. At themelt-to-vapor interface the density increases, driven by an increase in themagnitude of the density-dependent embedding-energy contribution to thecohesive energy of the metal. This behavior is in contrast to that found at themelt-to-vapor interface of nonmetallic systems.