On reasons for the hysteresis of melting and crystallization of nanoparticles

Molecular dynamics experiments for metal nanoclusters (gold, nickel, and aluminum) with the tight-binding potential have indicated that the melting temperature increases noticeably and the crystallization temperature decreases significantly with an increase in the absolute value of the heating and cooling rates, respectively. It has been concluded that the pronounced hysteresis of melting and crystallization is due primarily to nonequilibrium conditions of heating and cooling, but it is incompletely eliminated by reducing the rate of variation of the temperature. It has been found that the hysteresis of melting and crystallization corresponds at the structural level to a smooth crossover from the liquid state to the crystal one.