Study on size effect of melting temperature of Pb nanowires

The size dependent melting temperature(M.T.) of Pb nanowires is studied by molecular dynamics simulation method.It is found that the M.T.of Pb nanowires decrease with decreasing the size.The melting process starts from the surface,and then approaches to the center of the wires.It is shown that the M.T.increases during the melting process,which is different from the melting of bulk Pb.Furthermore,the M.T.variation ratio between Pb wires and films is 2∶1 in identical size.Furthermore,it is found that there exists a critical size S(2nmS2.5nm).The stable structure is crystal with size larger than S,and is amorphous with size smaller than S.