The Adsorption of C$_{60}$ fullerene molecules on Nanostructured Au (111)

The sub-monolayer growth of C$_{60}$ molecules on the Au (111) surface has been studied using STM in ultra high vacuum. The C$_{60}$ molecules tend to form close-packed layers due to a strong inter-molecular interaction. However, within the close-packed layer, there are finer, secondary structures that are specific to each of all the three C$_{60}$/Au interfacial structures ((2$\surd $3$\times $2$\surd $3)R30\r{ }, in-phase (R0\r{ }) and R14\r{ }) observed [1]. This is a consequence of the molecule-substrate interaction and our findings demonstrate a much more complex structural variation at the molecule-substrate interface than previously assumed. Furthermore, within the R14\r{ } C$_{60}$ layer, slightly darker molecules (30 pm lower) aligned along the \~{a}11-2\~{o} direction with a $\sim $6 nm spacing are observed and these molecules are arranged in a reasonably well-ordered two-dimensional lattice. C$_{60}$ molecules are also found to decorate the elbow sites of the herringbone reconstructed Au(111) even at room, and when fullerenes are deposited to arrays of fabricated monolayer gold stripes (gold-fingers) [2], the molecules show step-specific attachment where the step edges with the (111) micro-facet are preferentially populated.\\[0pt] [1] X. Zhang, F. Yin, R. E. Palmer and Q. Guo, \textit{Surf. Sci.} 602 (2008) 885-892.\\[0pt] [2] Q. Guo, F. Yin and R. E. Palmer, \textit{Small} 1 (2005) 76-79.