Stick-Sudden-Rotation And Structural Polymorphism Of (C-70)(M)-(Au)(N) Hybrid Nanoclusters

We fabricated magic number (C-70)(m)-(Au)(n) clusters on the Au(111) substrate. These clusters are stable at room temperature but display unpredictable rotational movement. The time duration between two successive rotations is in the order of similar to hour. The cluster rotation is a thermally activated process due to energy fluctuation, which is more significant for small clusters. We followed the rotational movement of (C-70)(10)-(Au)(35) clusters using scanning tunneling microscopy. Our observation suggests that thermal fluctuation leads to rapid diffusion of Au atoms at the edges of the cluster and the cluster has many metastable configurations associated with structural polymorphism.