Cyclic voltammetry interaction effects

An important feature of the rotaxane in Scheme 9.12 is that the translocation of the macrocycle is also achieved by the reduction of the fullerene to its trianion, which is both effected and observed by cyclic voltammetry. In DMSO, the proximity of the macrocycle to the fullerene stabilized substantially the electrogenerated trianion (A i/2 = 46 mV) through n—n interactions. Surprisingly, in THF where the macrocycle is preferentially positioned on the peptide station, a similar behavior was... 

In the same sense, at negatively charged edge-plane graphite electrodes, faradaic response of plastocyanin is normally not obtained due to the repulsive coulombic interactions. However, upon addition of a small amount of a redox-inactive multivalent cation, i.e., Mg +, stable and well-behaved cyclic voltammetry is observed (35). Extensive investigations of anionic proteins revealed (27,36) that the effectiveness of promotion is in the order of s> M. These effects... 

Cyclic voltammetry and differential pulse polarography have been used to investigate the redox properties of the di-Ni(II) species in acetonitrile. Effectively, a two-electron step was observed for the complex of 30, whereas that of 29 (n = 2) yielded two clear one-electron steps. This is in accord with the occurrence of an interaction between the nickel sites for the latter system containing the shorter link between the isocyclams. 

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