Observation of single molecule transport at surfaces via scanning microscopies: Monte Carlo wave function study of a model problem.
We discuss experiments where the trajectories of individual molecules or atoms at surfaces are observed by means of scanning microscopy. A scanning probe moves along the surface and excites the molecule so that the molecule's location is deduced from the times at which fluorescence photons are emitted. Operation of other types of scanning microscopes can be described by similar models. The observed trajectories are inherently affected by the interaction between the molecule and the probe such that the measured diffusion coefficient depends on the frequency at which the surface is scanned. The number of photons emitted by the molecule during a scan is affected in a nontrivial way by its mobility. If photoexcitation increases the mobility, we find emission to be suppressed.
Makarov
Dmitrii E
DE
Department of Chemistry and Biochemistry and Institute for Theoretical Chemistry, University of Texas at Austin, Austin, Texas 78712, USA.