The xenon sensitised radiolysls of HBr

Abstract

SURJIT S. NAGRA and DAVID ANTHONY ARMSTRONG. Can. J. Chem. 54, 3592 (1976).The 60C07,-radiolysis of mixtures of HBr with Xe has been investigated at room temperature. lonisation measurenlents and hgdrogen yields provide strong eLidence for energy transfers between the two components. The small but significant decrease in ionisation yields at low HBr:Xe is independent of total pressure and consistent with a competition between HBr and Xe for the Hornbeck-hlolnar states of Xe. The increase in ionisation lields at higher HBr:Xe ( Z above 0.2) is probably due to collisionally-induced ionisation or chemi-ionisation reactions of highly excited states of HBr.As in pre~iously reported experiments with W2S the hydrogen yields from HBr are strongly enhanced in the presence of Xe. The maximum sensitisation of 4 inolecules of H ? per 100 eV can be explained by energy transfer froni excited states of Xe (G -2.5) and subexcitation electrons having energy between 4.3-8.3 eV (G -1.5) in Xe. The results obtained from thermal electron scavenging with SF6 confirin previous findings that inert gases are inefficient a t moderating electrons to thermal energies. At Iligh [SF6] [HBr]. SF6 interferes with hydrogen-forming reactions other than those of electrons.SURJIT S. NAGRA et DAVID ANTHONY ARMSTRONG. Can. J. Chem. 54, 3592 (1976).