Detection of Tight ion-Pair in Some Novel Lipopathic Oxidants from the Monolayer at Air-Water Interface

Abstract

From the isotherms of surface pressure and area of cetyltrimethylammonium dichromate, permanganate and cerie nitrate, the anchoring area on water-air interface for each oxidant has been determined by spreading as Langmuir monolayer. The area/molecule of these oxidants with a common amphiphilic counterion, i.e., cetyltrimethylammonium ion, depends on the size of the anion counterpart indicating the existence of contact ion pair between CTA+ and the anionic group in aqueous medium. However, in aqueous acetic acid subphase, the decrease in area/molecule of cetyltrimethylammonium dichromate indicates dissociation of the constituting ions