Room-temperature scanning tunneling microscopy manipulation of single C₆₀ molecules at the liquid-solid interface: Playing nanosoccer

This scanning tunneling microscopy (STM) study uses a supramolecular two-dimensional architecture of trimesic acid molecules adsorbed on a graphite substrate as a host for the incorporation of C₆₀ as a molecular guest. By choosing a proper solvent, it was possible to verify that self-assembly of the host-guest structure can be accomplished at the liquid solid interface. Because of the ideal steric match with the molecular bearing of the host structure, C₆₀ buckminster fullerenes are feasible guests. It was possible to coadsorb C₆₀ within cavities of the open TMA structure from the liquid phase, and lateral manipulation of the molecular guest by the STM tip was demonstrated at room temperature. Because of the increased tip-sample interaction as a result of lower tunneling resistance, a transfer of a C₆₀ molecule from one cavity of the host structure to an adjacent one was achieved.