交流伏安法 （ACV） 因其能够提高电化学合成的产量以及提高电分析测量灵敏度的能力而越来越受欢迎。ACV 的主要分析优势之一是它能够以施加频率的整数倍（谐波）产生交流电，从而有效地同时收集多个数据集。然而，由于缺乏统一的理论来预测任意反应方案的高次谐波，因此阻碍了 ACV 数据的解释。为了满足对 ACV 数据进行定量解释的需要，本文概述了一种预测具有最多两个电荷转移事件和任意数量的一阶化学反应平衡的系统任意数量谐波的方法。对于各种单步和两步电荷转移方案，给出了到三次谐波的结果，对于二聚化和歧化的二阶情况，给出了基波谐波的结果。在复平面中可视化交流电，同时考虑电流的大小和相位角，通常会揭示有关电化学方案的信息，而这些信息很难从单独的交流电大小的图中辨别出来。通常，不可逆电荷转移会导致较小的相位角，而耦合化学反应会导致复平面 ACV 图的纵横比变得更加圆。每个方案在 ACV 数据中都有自己的指纹，这些指纹提供了有关电荷转移过程中给定时刻主要化学反应的宝贵信息。
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Alternating Current Voltammetry: Predicting and Visualizing Harmonics
Alternating current voltammetry (ACV) is gaining popularity for its ability to improve the yield of electrochemical syntheses, and for its ability to improve the sensitivity of electroanalytical measurements. Chief among the analytical advantages of ACV is its ability to generate an alternating current at integer multiples (harmonics) of the applied frequency, effectively gathering several datasets at once. However, interpretation of ACV data is hindered by the lack of a unified theory to predict higher harmonics for arbitrary reaction schemes. To meet the need for quantitative interpretation of ACV data, the present paper outlines a method for predicting an arbitrary number of harmonics for systems with up to two charge transfer events and any number of first-order chemical reaction equilibria. Results are presented up to the third harmonic for a variety of single-step and two-step charge transfer schemes, and results for the fundamental harmonic are presented for the second-order cases of dimerization and disproportionation. Visualizing the alternating current in the complex plane, accounting for both the magnitude and the phase angle of the current, frequently reveals information about an electrochemical scheme that is difficult to discern from plots of the alternating current magnitude alone. In general, irreversible charge transfer causes smaller phase angles, and coupled chemical reactions cause the aspect ratios of complex-plane ACV plots to become more circular. Each scheme has its own fingerprint in ACV data, and these fingerprints give valuable information about the dominant chemical reaction at a given moment during charge transfer.
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