Molecular resolution imaging of C₆₀ on Au(111) by non-contact atomic force microscopy

Non-contact atomic force microscopy (NC-AFM) was used to study thin films of C₆₀ on Au(111). After observing the Au(111) 23 × √3 reconstruction, 2-3 monolayers of C₆₀ were deposited onto the Au surface. The close-packed C₆₀ surface was imaged by NC-AFM with molecular resolution. Enhanced corrugation and a stretching of the C₆₀ lattice were observed at step edges. Based on a calculation of the force required to displace an edge molecule, it is proposed that the edge effects are a result of tip-induced displacements of edge molecules. While imaging small clusters of C₆₀, some molecules were removed, leading to structural rearrangements of the clusters.