COMPARATIVE-STUDY BETWEEN THE GENERAL-SOLUTIONS PRESENTED IN THE LITERATURE FOR THE DOUBLE-PULSE PROBLEM FOR A SLOW CHARGE-TRANSFER REACTION

A detailed comparative study between the three general solutions in cl osed form for the double-pulse problem for a slow charge transfer reac tion derived in the literature (M. Lovric and J. Osteryoung, Electroch im Acta 25, 96 (1982); Fatouros et al., J. electrcanal. Chem. 247, 37 (1988); and J. Galvez and M. L. Alcaraz, Electrochim. Acta (submitted) ) is presented. Representative voltammograms to six significant figure s for the most widely used pulse techniques, differential pulse polaro graphy, differential normal pulse polarography, and reverse pulse pola rography, as well as for the less familiar forward reaction rate contr olled, backward reaction diffusion controlled mode, have been obtained . These results make clear that although an analytical correspondence between these solutions has not been established, they can be consider ed equivalent, at least numerically. For computation purposes, however , the behavior of these solutions is quite different, and their streng ths and weaknesses are discussed. Finally, by comparing the results ob tained with our former solution to this problem (J. Galvez et al., J. electroanal. Chem. 205, 21 (1986)) with those calculated from the gene ral solution, allowed us to establish the conditions where the simplif ied equation can be used with certainty.