Evidence of the Interfacial Parameter Scale

AX is proportional to the modifications occurring at the interface with respect to the separate phases. Therefore any events occurring at the interface should in some way be influenced by AX or should to some extent reflect AX. 

The meaning attached to A is precisely that of the cpd at the metal/so-lution interface, i.e., X measures the change in P of a given metal as it is covered with a macroscopic film of solution at o - 0. The cpd, A4 - X, includes a contribution from metal electrons and from solvent dipoles. While it may be difficult to compare the behavior of different metals, as Figs. 21 and 22 show, because of the lack of a parameter unambiguously 

Jaworski Electrochim. Acta 34 486, Fig. 2, 1989, Copyright 1989 with permission of Elsevier Science.) 

It is an experimental fact that the capacitance of an electrode in a given solvent is a function of the nature of the metal. This was pointed out by Frumkin et al,333 and has been discussed several times in the literature.7 349 94 99 999 Trasatti34 901 showed that the reciprocal of the differential capacitance at a = 0 is linearly correlated with the strength of the metal-water interaction. The reader is referred to the original papers for a detailed discussion. 

The idea is that X must govern in some way all properties of the interface, including the permittivity. The latter includes an electronic and a molecular term, which have been tentatively separated7 on the basis of model approaches. In this chapter, only the correlation of the capacitance with X is relevant. The correlation between 11C and tX has been demonstrated for eight metals in aqueous solution. It has been shown26,34 that the correlation derived from sp-metals is fit also by single-crystal faces of sd-metals. In particular, the capacitance of Ag increases in the sequence 

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