Can FT revolutionize voltammetric techniques as it did for NMR? The linear, staircase, and cyclic modes of dc voltammetry have become the electrochemical methods of choice for rapidly gaining insights into the mechanistic details of the electron-transfer processes that are significant in chemistry, biology, physics, industrial chemistry, and other disciplines (1-4). In this article, we will show how a variety of voltammetric techniques that are often considered quite unlike really differ only in the combination of sine waves superimposed onto a dc potential. Because of this characteristic, instrumentation and simulations only need the capacity to generate a dc ramp and sine waves of any combination of frequencies and amplitudes. Also, the data obtained in the time domain can be transformed into the frequency domain to achieve a major level of unification in voltammetric methods. In this integrated approach, differences in techniques are now represented by mechanism-dependent patterns of behavior detected at frequencies that are related to the input signal. Thus, differences are no longer related to the use of small- or large-amplitude considerations, and nonlinearity—often regarded as a complicating factor—is now seen as a distinct advantage.
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