JOURNAL OF PHYSICAL CHEMISTRY C, cilt.123, sa.20, ss.12791-12796, 2019 (SCI-Expanded)
We fabricated magic number (C70)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 ~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 (C70)10-(Au)35 clusters using scanning tunnelling 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 meta-stable configurations associated with structural polymorphism.