SCANNING TUNNELING AND ATOMIC-FORCE MICROSCOPY PROBES OF SELF-ASSEMBLED, PHYSISORBED MONOLAYERS - PEEKING AT THE PEAKS

The imaging and control of self-assembled, physisorbed monolayers have been the subject of numerous scanning tunneling microscopy and atomic force microscopy investigations. The successful interpretation of the structures observed in scanning probe images of molecules self-assemb led at liquid-solid and gas-solid interfaces has benefited greatly fro m recent experimental and theoretical work. These studies are convergi ng on a general tunneling mechanism that accounts for the images of we akly bound, insulating adsorbates. Experiments in which the dynamical behavior of these monolayers has been monitored as a function of time both statically and after the introduction of an external perturbation are described, and novel studies of the selective control of monolaye r structure that make use of internal and external electric fields, ph otons, and solvent coadsorption are reviewed.