Conductance of two simple ionic species

Eq.(5.98) is derived from the expression reported in ref. [13] which contained individual cut-off distances and second-order terms. It is a simplification of the latter in the sense that it is limited to the first-order term and it is written as a function of a mean cut-off distance. It is this simplified expression which was used in the subchapter Conductance of two simple ionic species . 

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