Molecular dynamics simulations have been used to study the melting of the nanometer Pdn(n=13
14
54
55)clusters.We found that these Pdn clusters all have pre-melting phenomenon.The melting temperature of cluster does not simply increase with increasing the number of atoms in cluster.The Pdn(n=54
55)cluster have narrow pre-mleting tempreture intervals.Pdn(n=13
54
55)clusters have solid-liquid coexistence and Pd14 cluster shows a surface melting phenomenon.
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