Calculation of adiabatic free energy surfaces in the case of electrochemical tunneling microscopy of redox systems

A method of adiabatic (infinitely slow) switching-on of interaction of the reactant with the electrode and the tip of a tunneling microscope at a bias voltage other than zero is used to derive expressions for the average number of electrons in the valence orbital of the reactant, the current passing through the valence orbital of the reactant at fixed values of coordinates of the slow subsystem of the solvent, and the electronic contribution to an expression that describes the adiabatic free energy surface (AFES) of the electrode-reactant-tip of the tunneling microscope system. The derived expressions are the same that had already been obtained in a Kuznetsov-Schmickler work, by a not-quite-correct method, though. Relationships that link the AFES corresponding to the opposite signs of the bias voltage are deduced. Examples of calculations of AFES and a current for a number of characteristic sets of parameters of the system are presented.Translated from Elektrokhimiya, Vol. 41, No. 3, 2005, pp. 259–272.Original Russian Text Copyright © 2005 by Medvedev.