The Radiolysis and Photolysis of Methanolic Solutions of Eosin. I. The γ-Radiolysis of Neutral and Alkaline Solutions

Abstract The γ-radiolysis of eosin has been studied in deaerated neutral and alkaline methanolic solutions. Eosin is reduced principally with CH2OH radicals in dilute solutions. In neutral solutions, G(–eosin) is about 2 at the eosin concentration of 10−5m and increases as the concentration of eosin is increased. The final products are leuco-eosin and an unidentified substance which has an absorption peak at 455 nm. In an alkaline solution (10−5m), G(–eosin) is about 4 and the product is semireduced eosin, which is stable in the dark and which undergoes photo-debromination. The ESR spectrum of semireduced eosin has also been recorded. Comparative studies have also been made on uranin solutions.