Growth of two-dimensional C60 nano clusters within a propylthiolate matrix

Two-dimensional C60 clusters embedded in a propylthiolate/Au(111) self-assembled monolayer (SAM) are produced by depositing C¬60 molecules on top of the SAM at 110 K followed by thermal annealing to room temperature. The SAM acts as a spacer layer at 110 K preventing C60 molecules from reaching the Au(111) substrate. As temperature is increased, molecular scale vacancies open up within the SAM allowing C60 molecules to drop to the surface of the Au(111) substrate. This initial “rooting” is then followed by the formation of two-dimensional C60 clusters. The clusters have a rather uniform orientation with a well-defined direction for the close-packed C60 molecules.