Size-dependent melting properties of free silver nanoclusters

The melting properties of free nanoclusters of silver atoms interacting thr ough an analytic embedded-atom method type potential are studied by using m olecular dynamics simulations. The particle-size-dependent depression of th e melting temperature T-m of Ag258-3871 can be explained by the surface pre melting models (SPM). The melting process of Ag-13 (178) changes significan tly compare with that of Ag258-3871, in which T-m deviate from the values p redicted from the SPM and the latent heat of fusion Delta mu (ls) enhance g reatly. For the first time, the size-dependent variations in T-m and A mu ( ls) for free neutral nanoclusters with r less than or equal to r(c) (r(c) i s critical radius) is presented and a new intermediate melting mechanism is identified. In addition, a reentrant morphology transition in Ag-147, quas imelten phases of Ag13-55, and icosahedral precursors to the melting of Ag1 3-309 are also recovered.