Morphology of C60 thin films grown on Ag(001)

The morphology of C60 films deposited on a Ag(001) single crystal has been studied using an UHV-STM. The C60 molecules are arranged in a quasi-hexagonal c(6 x 4) structure, having the long axis along the (110) direction of the Ag surface. Due to the existence of two equivalent directions, the C60 film presents different domains, separated by dislocation lines. In each domain, peculiar structures of bright C60 molecules have been resolved. These structures are due not to geometric effects, but to nonhomogeneous charge distributions and different chemical bonding with the Ag substrate. (C) 1998 Elsevier Science B.V. All rights reserved.