| Abstract
| - Theoretical expressions are presented corresponding to the response of adsorbed molecules which exhibita quasi-reversible or totally irreversible charge transfer in cyclic reciprocal derivative chronopotentiometrywith exponential currents (CRDEC). The higher and better defined peaks obtained in CRDCEC comparedwith those obtained in cyclic voltammetry (CV) indicate that CRDEC could be considered as a powerfultool in the characterization of molecular films. Although reciprocal derivative chronopotentiometry withconstant current (RDC) enjoys at present an extensive use in the elucidation of electrode processes, whenthis technique is applied to adsorbed molecules exhibiting an irreversible charge transfer, peaks are notobserved. Under these conditions, RDCEC turns out to be more suitable than RDC. Furthermore, the useof programmed currents makes the selection of an appropriate range of transition times easier than doesthe use of constant currents. Equations for the peak currents, peak potentials, ratio between peak heights,and difference between peak potentials of successive responses corresponding to two exponential currentsof opposite signs have been applied to the determination of the kinetic parameters of the experimentalsystem azobenzene in protic media.
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