A molecular dynamics demonstration of annealing to a perfect C60 structure

The formation process of imperfect fullerenes C-60 and C-70 was simulated using the molecular dynamics method as described in our previous report. These imperfect fullerenes were kept at 2500 K to evaluate annealing effects. Through successive Stone-Wales transformations, perfect fullerene structures were achieved both for C-60 and C-70 in about 200 ns. The annealing temperature and time scale were plausible, compared to experimental conditions as seen in an Arrhenius plot. Similar simulations were performed for smaller clusters at each stage of the clustering process. Based on these simulations, a fullerene formation model is proposed. (C) 1998 Elsevier Science B.V.