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.