SCANNING-TUNNELING-MICROSCOPY OF C-60 AL(111)-6X6 - INEQUIVALENT MOLECULAR SITES AND ELECTRONIC-STRUCTURES/

We present a scanning tunneling microscopy and spectroscopy (STM/S) st udy of a thermally stable, annealed monolayer of C-60 On Al(111). The C-60 molecules are arranged into a close-packed hexagonal layer of 2 r oot 3 x 2 root 3 periodicity with the symmetry reduced to 6 x 6 as a r esult of a substrate reconstruction which raises one third of the full erenes. Molecularly resolved tunnelling spectroscopy provides experime ntal evidence for the geometrical displacement in height and shows dra matic differences between the electronic structure of the fullerenes i n the two inequivalent adsorption sites.