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Pure & Appl. Chem., Vol. 45, pp. 81-97. Pergamon Press, 1976. Printed in Great Britain. INTERNATIONAL UNION OF PURE AND APPLIED CHEMISTRY ANALYTICAL CHEMISTRY DIVISION COMMISSION ON ELECTROANALYTICAL CHEMISTRY CLASSIFICATION AND NOMENCLATURE OF ELECTROANALYTICAL TECHNIQUES (RULES APPROVED 1975) PERGAMON PRESS OXFORD · NEW YORK · PARIS · FRANKFURT ANALYTICAL CHEMISTRY DIVISION COMMISSION ON ELECTROANALYTICAL CHEMISTRYt CLASSIFICATION AND NOMENCLATURE OF ELECTROANALYTICAL TECHNIQUES (RULES APPROVED 1975) At the XXVth Conference of the International Union of Pure and Applied Chemistry in 1969, Commission V.5 on Electroanalytical Chemistry requested Profs. L. Meites, H. W. Nürnberg and P. Zuman to revise and up-date the recommendations on electroanalytical classification and nomenclature made by P. Delahay, G. Chariot and H. A. Laitinen [Anal. Chem., 32 (6), 103A (I960)]. Almost without exception, the recommendations made here are descriptive rather than prescriptive, in the sense that they reflect what seem to be the best—the most accurate, informative, and logical—of the names that have gained some currency in the prior literature. Many of these techniques, probably including polarography itself, would be unlikely to be given the names here recommended if they were just being developed now. Nevertheless their prior histories provide ample proof that those names are much too firmly established, both in the literature and in the minds of their users, to be dislodged. An attempt to develop a completely systematic and consistent nomenclature ab initio therefore seems futile and has not been made. This report follows the general lines of its predecessor, but deviates from it in a number of details. A slightly different classification is given in Table 1, and the other tables are differently arranged accordingly. Many techniques that have been developed, or that have become important in analysis or fundamental research, since 1960 have been added, and a few older or less important techniques are also included for the sake of completeness. As much of the nomenclature recommended by Delahay, Chariot, and Laitinen has been retained as seemed possible, but several deviations therefrom are to be noted. The term "polarographic titration" has not been accepted in place of either "amperometric titration" or "polarometric titration" and is accordingly withdrawn. The terms "biamperometric" and "bipotentiometric" are withdrawn, although they have been more widely used than "polarographic titration", because most of the colleagues we consulted thought them objectionable on the ground that they seemed to denote measurements of two currents or potential differences, respectively. Their replacements, "amperometry with two indicator elec- Table 1. Classification of electroanalytical techniques 1. Techniques in which neither the electrical double layer nor any electrode reaction need be considered (Table 2) 2. Techniques that involve double-layer phenomena but in which any electrode reactions need not be considered (Table 3) 3. Techniques involving electrode reactions A. Techniques involving electrode reactions and employing constant excitation signals (Table 4) B. Techniques involving electrode reactions and employing variable excitation signals 1. Variable excitation signals of large amplitude (usually considerably larger than 2x2,3RT/F volt, approximately 0-12 V at 25°C) (Table 5) 2. Variable excitation signals of small amplitude (usually considerably smaller than 2,3RT/F volt, approximately 0-06 V at 25°C) (Table 6) trodes" and "potentiometry with two indicator electrodes," contain more syllables, but it is hardly possible to suppose that both conciseness and reasonable accuracy can be achieved for any but a few of the techniques covered here. It is recommended that the term "polarography" be used to denote the s