Molecular Dynamics Simulation on Melting of Metal Cluster with Small Size

The melting processes of little size metal clusters were simulated by molecular dynamics method. The atomic interaction was described by embedded atom method (EAM). The root-mean-square (rms) bond length fluctuation and heat capacity versus temperature in heating were calculated. The melting processes of face centered cubic (FCC) Au clusters with 55 and 56 atoms are very similar. But those FCC Cu clusters with same size show different trends. Cu55 and Cu56 clusters have structure transitions from FCC structures to icosahedrons during heating processes. Due to one more atom than Cu55 on surface, Cu56 has a pre-melting process. The heat capacity curve of Cu56 has also one more peak than that of Cu55. All the results show that the small cluster's solid-liquid transition of the small clusters depends on atom type, structure, and atom number of the cluster.