point of zero charge (p.z.c.)

A surface charge is at its point of zero charge when the @S06159@ is zero. It is a value of the negative logarithm of the activity in the bulk of the charge-determining ions.
PAC, 1991, 63, 895. (Nomenclature, symbols, definitions and measurements for electrified interfaces in aqueous dispersions of solids (Recommendations 1991)) on page 902 [Terms] [Paper]