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In cyclic voltammetry, the Randles–Sevcik equation describes the effect of scan rate on the peak current ''ip''. For simple redox events such as the ferrocene/ferrocenium couple, ''ip'' depends not only on the concentration and diffusional properties of the electroactive species but also on scan rate.〔P. Zanello, "Inorganic Electrochemistry: Theory, Practice and Application" The Royal Society of Chemistry 2003. ISBN 0-85404-661-5〕 Or if the solution is at 25 °C:〔Crouch, Stanley R and Skoog, Douglas A: "Principles of instrumental analysis" Cengage Learning 2006, ISBN 0-49501-201-7〕 *''ip'' = current maximum in amps *''n'' = number of electrons transferred in the redox event (usually 1) *''A'' = electrode area in cm2 *''F'' = Faraday Constant in C mol−1 *''D'' = diffusion coefficient in cm2/s *''C'' = concentration in mol/cm3 *''ν'' = scan rate in V/s *''R'' = Gas constant in VC K−1 mol−1 *''T'' = temperature in K For novices in electrochemistry, the predictions of this equation appear counter-intuitive, i.e. that ''ip'' increases at faster voltage scan rates. It is important to remember that current, i, is charge (or electrons passed) per unit time. Therefore, at faster voltage scan rates the charge passed per unit time is greater, hence an increase in ip, while the total amount of charge is the same. ==Uses== Using the relationships defined by this equation, the diffusion coefficient of the electroactive species can be determined. Linear plots of ''ip'' vs. ''ν''1/2 provide evidence for a chemically reversible redox process vs the cases where redox causes major structural change in the analyte. For species where the diffusion coefficient is known (or can be estimated), the slope of the plot of ''ip'' vs. ''ν''1/2 provides information into the stoichiometry of the redox process. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Randles–Sevcik equation」の詳細全文を読む スポンサード リンク
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