The locus of the electrical centres of specifically adsorbed ions.
Source:
PAC, 1991, 63, 895
(Nomenclature, symbols, definitions and measurements for electrified interfaces in
aqueous dispersions of solids (Recommendations 1991))
on page 899
PAC, 1986, 58, 437
(Interphases in systems of conducting phases (Recommendations 1985))
on page 448