Ions become specifically adsorbed when short-range interactions between them and the
interphase become important. They are believed then to penetrate into the inner layer and may
(but not necessarily) come into contact with the surface. They are usually assumed
to form a partial or complete
monolayer.
Source:
PAC, 1986, 58, 437
(Interphases in systems of conducting phases (Recommendations 1985))
on page 448