Effect of Gamma- and X-Rays on Dilute Aqueous Solutions of Acrylonitrile

Abstract

THE immediate effect of the absorption of highenergy radiation (α-, β-, γ- and X-rays, fast protons, deuterons, etc.) by water is the ejection of electrons from the water molecules lying along the tracks of the rays. There has been much discussion concerning the mechanism of the chemical changes which occur in water or dilute aqueous solution as a result of this ‘primary radiochemical act’. Many of the investigations¹ have been concerned primarily with measurement of the ion pair yield (M/N is number of product molecules formed or reactant molecules decomposed per ion pair), and for such purposes it was sufficient to regard the radiation as producing ‘activated water’², an unspecified intermediate capable of bringing about the observed changes and formed in amounts proportional to the dose. Recent reconsideration of the types of chemical reactions undergone by the solutes has led to the view, proposed by Weiss and now widely held³, that the activated water consists of a hydrogen atom and hydroxyl radical, formed possibly by direct dissociation of water, or by electron capture and ion breakdown processes such as