Equation corrected Ilkovic

The original IlkoviC equation neglects the effect on the diffusion current of the curvature of the mercury surface. This may be allowed for by multiplying the right-hand side of the equation by (1 + ADl/2 t1/6 m 1/3), where A is a constant and has a value of 39. The correction is not large (the expression in parentheses usually has a value between 1.05 and 1.15) and account need only be taken of it in very accurate work. 

Derivations based on the introduction of this modified equation lead to a small correction factor within the Ilkovic equation, viz.,... 

Firstly, owing to the importance of the Ilkovic equation, we follow Ilkovic s argument [52] in the calculation of the limiting current, which although not completely rigorous, was later shown by MacGillavry and Rideal [53] to be correct under Ilkovic s assumptions. There are three steps to the argument. 

The left-hand side of the above equation gives the Ilkovic expression. It is thus possible to consider the right-hand side as correction terms to the Ilkovib equation. These corrections must take into account spherical diffusion, solution depletion in the neighbourhood of the drop due to previous drops, contact area with and shielding due to the capillary, and solution stirring. 

None of these assumptions is absolutely correct but more advanced theories produce equations very close to that of Ilkovic and with the same concentration dependence. 

For a diffusion-controlled reversible system, which does not involve semiquinone formation or dimerization of either the oxidized or the reduced forms, the correct shape of the polarographic current-potential curve is described by an equation derived by Heyrovsky and Ilkovic [cf. Eq. (70)] ... 

It has been shown recently that in the derivation of the simple IlkoviC equation, some factors have been neglected, and that for the most accurate theoretical calculations an additional correcting factor must be considered. For all practical purposes the above form is completely satisfactory. 

KouteckJ J (1953) Correction for spherical diffusion to the IlkoviC equation. Czech J Phys 2 50. 

Newman J (1967) Note. The Koutecky correction to the IlkoviC equation. 

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