Current capabilities in measurement precision

The measurement precision attainable for Ep and Ep/2 on a well-defined kinetic system has been reported recently by Eliason and Parker [55]. The system chosen as a model was the protonation of the 1,1-diphenyl-ethylene anion radical by methanol which, in DMF, had earlier been shown by Lerflaten and Parker [56] to follow the mechanism 

Results obtained for Epf2 at two values of v, 0.100 and 1.00 V s-1, at a substrate concentration of 1 mM are summarized in Table 7. The numbers in parentheses in the second column are the standard deviations in six replicate Ep/2 determinations, which can be seen to be negligibly small. The experiments gave 5 values of AEP/A log v with a mean of 28.68 and a standard deviation of 0.11 mV decade-1. The theoretical value for the mechanism in eqns. (39)—(41) under the conditions of the measurements is 28.95 mV decade-1. A similar set of experiments was carried out in which the substrate concentration was varied from 0.125 to 4.00 mM (Table 8). In this case, the mean value was 28.53 with a standard deviation of 0.23 mV decade-1. The numbers in parentheses are standard deviations 

Typical linear sweep voltammetry data for the reduction of 1,1-diphenylethylene in N, JV-dimethylformamide in the presence of methanol3 

A comparison of LSV slopes obtained from peak and half-peak potential measurements6 

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