Journal of Physical Chemistry B, Vol.108, No.47, 18129-18134, 2004
Nanowiring by molecules
Microelectronic sensors require the nanowiring of a selectively active site to an electrode. Different molecules can be used as the bridge that establishes the electrical communication. We report computational results for the current carried by molecules tethered between two gold clusters as a function of the overvoltage. The computations include the effect of the voltage at the ab initio level. The trends are consistent with the currents as measured by electrochemical means and suggest that the rate of charge migration can reach far higher values than measured given somewhat higher applied bias or the application of a gate voltage. The role of polarization of the molecular charge density by the applied voltage can be quite significant with definite propensity for the orientation of the molecular charge density with respect to the field. Conduction spectroscopy is therefore analogous to optical spectroscopy in strong laser fields where the field is not a weak probe but C dresses the system and can be used to control it.