Size dependence of the coalescence and melting of iron clusters: A molecular-dynamics study

Molecular-dynamics simulations show that the coalescence of iron nanoclusters (FeN+FeN→Fe2N, where up to 2N=10 000 atoms, or a diameter of 60.3em0exnm, has been studied) occurs at the temperatures lower than the cluster melting point, and that the difference between coalescence and melting temperatures increases with decreasing cluster size. Thus, the temperature at which small metal nanoclusters are observed to coalescence, e.g., in the experimental growth of carbon nanotubes, is not the same as their melting point.