Melting of Bulk Gold During Continuous Heating: A Molecular Dynamics Study

Molecular dynamics simulations with Quantum Sutton- Chen many body potential are employed to study the melting behaviors of bulk gold at different heating rates within NPT ensemble. Not only gold crystals but also gold crystals with defects are studied. Results indicate that the superheating and melting behaviors of bulk gold are strongly affected by the heating rate. Heating rate enhanced diffusion is observed and analyzed. The randomization induced by heating rate enhanced diffusion should be the main driving force to eliminate the energy barrier for phase transition to occur. And the upper limit of superheating during continuous heating should be the temperature at which the energy rise resulting from the heating rate enhanced diffusion equals the energy barrier for phase transition to take place.