Freezing of silver cluster and nanowire: A comparison study by molecular dynamics simulation

The crystallization of liquid Ag cluster and nanowire, about 2.3 nm in diameter, has been studied by molecular dynamics simulation at three different cooling rates (i.e., 2 × 1013 K/s, 2 × 1012 K/s, 2 × 1011 K/s). It is found that the structure of Ag cluster in the specified size changes from amorphous to crystalline directly during the cooling process, rather than follows the route of amorphous–icosahedra–crystalline. The Ag nanowire in the specified size also changes from amorphous to crystalline directly, rather than follows the route of amorphous–(multi-shelled)–crystalline. All the finial structures of Ag cluster and nanowire after relaxation are FCC despite the different cooling rates, which means that the FCC is the most stable structure. Furthermore, the crystallization temperature of Ag nanowire is higher than that of cluster at the same cooling rate, which suggests that the crystallization temperature is dimensional-dependent.