Intramolecular structures of C60 molecules adsorbed on the Cu(111)-(1 x 1) surface.

The structure of C 60 molecules adsorbed on the Cu(111)-(1×1) surface has been investigated by scanning tunneling microscopy (STM). Bias voltage dependent STM images of individual C 60 molecules in the monolayer film showed unique intramolecular structures with a threefold symmetry. The observed images agree well with those calculated using the local density approximation. With charge transfer from the Cu(111) substrate to the monolayer film, the C 60 molecule ratchets to threefold hollow sites