Fig. 2.

Stability evaluation and distant electron transfer. (A) Stability evaluation of the system represented by azurin/octanethiol/Au(111) subjected to successive cyclic voltammetry scans at 5 V·s^–1, equivalent to a redox switch frequency of ≈10 Hz. The relative charges were obtained by integrating the redox peaks and normalizing vs. the initial charge. (B) Distance-dependent ET kinetics shown by a plot of the rate constant (in natural logarithm) vs. the distance. The distance was estimated according to refs. 46 and 47 for the alkanethiolate lengths on the gold surface. The decay factors (defined as the rate decay per unit distance), obtained from the slopes (for long-chain alkanethiols, n > 8), were 0.83 and 0.91 Å^–1 in H₂O and D₂O media, respectively.