Abstract: This paper studies the coalescence of heteroclusters Au$_{767}$ and Ag$_{767}$ by using molecular dynamics with the embedded atom method, where layer atomic energy is employed to describe the potential energy variation of per atom in different layers along radial direction. The results show that the coalescence is driven by releasing the atomic energy of the coalesced zone. The deformation, which is induced by substitutional and vacancy diffusion during the coalescence, makes the coalesced cluster disorder. If the summation of the thermal energy and the released atomic energy is large enough to keep the disorder state, the clusters form a metastable liquid droplet; otherwise, the clusters coalesce into a solid cluster when the coalesced cluster reaches the equilibrium state, and the coalesced cluster experiences liquid to solid ordering changes during the coalescence of a solid Au$_{767}$ with a liquid Ag$_{767}$ and a liquid Au$_{767}$ with a liquid Ag$_{767}$. The centre of figure of the cluster system is shifted during the coalescence process, and higher coalescence temperature causes larger shift degree.

Key words: molecular dynamics, embedded atom method, heterocluster, coalescence