A theory for an electrode-associative ionic fluid interface is propose
d. It takes into account the effect of interionic pairing as well as p
acking and electrostatics. The theory is based on the use of Wertheim'
s two-density formalism, i.e., the ions are represented as free and as
sociated into dimers. Dimerization is made possible by the attractive
interaction between sites embedded in each ion. The results for ionic
density profiles calculated in a generalized exponential approximation
are given. Analytical expressions for the differential capacitance, p
otential drop and adsorption coefficient calculated in the mean spheri
cal approximation are presented.