ISOTOPE EFFECTS IN NEUTRAL H2O–D2O IRRADIATED SOLUTIONS AND THE NATURE OF THE REDUCING RADICAL

Abstract

Neutral solutions of sodium formate in H2O–D2O mixtures were irradiated by 200-kv X rays. The atomic deuterium isotope effect (αA) and its dependence on deuterium concentration were determined. In a 1 × 10−1 M HCOONa, 96% D2O solution, G(hydrogen) = 1.14 and αA = 4.3. It is concluded that the hydrogen atom cannot be formed from a single water molecule. Possible mechanisms of hydrogen atom formation are discussed. The alternative possibilities for the atoms to react as H or H2O− are viewed in the light of the proposed mechanisms.