Electron spin resonance studies of fundamental processes in radiation- and photo-chemistry. Part 6.—The radiolysis of acetic acid

Abstract

Matrix isolation studies on CH₃COOH, CH₃COOD and CD₃COOD, using e.s.r. to identify trapped radicals, suggest a mechanism for the γ-radiolysis of acetic acid at low temperatures. It is suggested that the primary anion, CH₃ĊOOH^–, which is the only species observed at –196°C, dissociates into CH₃CO^–₂ and H, the latter reacting further to give CH₃CO and H₂O. The molecular cation CH₃ĊOOH⁺ is not observed, but the CH₃ radicals observed in acetic acid/water matrices are thought to be decomposition products, together with CO₂. The mechanism proposed for radiolysis of the solid is also compatible with product yields obtained from radiolysis of the pure liquid.