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High-resolution electron-energy-loss spectroscopy ͑HREELS͒ has been used to characterize C 60 films up to 4 monolayers thick grown at room temperature on hydrogen-terminated Si͑100͒. Our results show that compared with C 60 films on clean Si͑100͒ surfaces a considerably higher degree of order in the as-deposited films is achieved. At low coverages the observed C 60 vibrational modes and the Si-H vibrations of the substrate are essentially unshifted, indicating a van der Waals-type interaction between C 60 and Si͑100͒H͑2ϫ1͒. After annealing at 450 K the film order is substantially increased. Annealing at 600 K results in desorption of the C 60 multilayers and a hydrogen-transfer reaction from the surface to the adsorbed monolayer molecules. When annealing the sample at 800 K, the remaining surface terminating hydrogen desorbs and evidence for a change in the C 60 bonding configuration is found. Finally, flashing the sample at 1300 K leads to the formation of silicon carbide.

Surfactant stabilized gold clusters have been deposited on graphite and studied with scanning tunneling microscopy in vacuum. Cluster layers with a superlattice constant of ≈31 Å were found, extending over several micrometers. The clusters form a hexagonal lattice which is ordered over distances of about 100 Å. At low sample biases (<0.75 V) the clusters are not imaged, consistent with a Coulomb blockade effect.

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