Second harmonic alternating current polarography. Considerations of the theory of quasi-reversible processes

Abstract

Results are presented of an extensive theoretical study of the second harmonic ac polarographic wave for systems involving rate control by diffusion and charge transfer kinetics (the quasi-reversible case). The expanding plane model of the dropping mercury electrode is employed. Emphasis is placed on aspects of the second harmonic response which have been considered only briefly in previous work such as the effects of a non-Nernstian dc process, the phase angle behavior, and the data analysis problem. The results make apparent the potentialities of second harmonic ac polarography in the study of quasi-reversible processes, particularly as a measurement which complements the more conventional dc and fundamental harmonic ac data.

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