Abstract
We have investigated the conductance of a single 4,4'-bipyridine molecule anchored on Au electrodes under electrochemical potential control. Appearance of the peak in the conductance histogram suggests the formation of a single molecular junction. The conductance of the single 4,4'-bipyridine molecular junction was estimated from the peak value of 0.01 G0 (G0=2e2/h) in the histogram. The conductance of the molecular junction did not change with the electrochemical potential. On the other hand, the intensity of the 0.01 G0 peak in the conductance histogram decreased as the potential of the Au electrode scanned from 0.2 V to -0.4 V vs. Ag/AgCl. The electrochemical potential dependence of the intensity of the peak in the conductance histogram could be explained by the change in the adsorption properties of 4,4'-bipyridine on the Au electrode.
