Crossover Site-Selectivity in the Adsorption of the Fullerene Derivative PCBM on Au(111)

With increasing coverage, self‐assembly of the fullerene derivative phenyl‐C61‐butyric acid methyl ester (PCBM) on Au(111) undergoes a transition from substrate‐controlled to hydrogen‐bond‐controlled. At low coverages, PCBM nucleates exclusively at the fcc areas of the “herringbone” reconstruction (left image). At higher coverages, double rows of PCBM molecules connected through hydrogen bonds are formed (right image). ML: monolayer.