Coalescence of heteroclusters Au767 and Ag767: a molecular-dynamics study

This paper studies the coalescence of heteroclusters Aumolecular dynamics, embedded atom method, heterocluster, coalescenceProject supported by the National Natural Science Foundation of China (Grant No 50374027), the program for New Century Excellent Talents in University of China (Grant No NCET-06-0289), and the 111 project of China (Grant No B07015).3640J, 61461/3/2008 12:00:00 AM3/6/2008 12:00:00 AMThis paper studies the coalescence of heteroclusters Aumolecular dynamics, embedded atom method, heterocluster, coalescenceProject supported by the National Natural Science Foundation of China (Grant No 50374027), the program for New Century Excellent Talents in University of China (Grant No NCET-06-0289), and the 111 project of China (Grant No B07015).3640J, 61461/3/2008 12:00:00 AM3/6/2008 12:00:00 AMThis 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.