Surface Geometry of C-60 on Ag(111)
Physical Review Letters 103(5): 056101
The geometry of adsorbed C-60 influences its collective properties. We report the first dynamical low-energy electron diffraction study to determine the geometry of a C-60 monolayer, Ag(111)-(2 root 3x2 root 3)30 degrees-C-60, and related density functional theory calculations. The stable monolayer has C-60 molecules in vacancies that result from the displacement of surface atoms. C-60 bonds with hexagons down, with their mirror planes parallel to that of the substrate. The results indicate that vacancy structures are the rule rather than the exception for C-60 monolayers on close-packed metal surfaces.