Behavior of Trapped Electrons in Irradiated 3-Methylpentane Glass at 77°K

Publisher Website
Google Scholar
Abstract
Formation and decay of trapped electrons in 3-methylpentane glass irradiated by γ rays were studied by the electron spin resonance method at 77°K. In pure 3-methylpentane, the trapped electrons decayed by first-order reactions. Observed decay curves are clearly the superposition of two reactions having the first-order rate constants of 0.2 and about 0.04 min−1, respectively. The yield of the trapped electrons (G value) is 0.14 for the fast decaying part and 0.09 for the slow decaying part. The addition of a small amount of 2-methylpentene-1 slowed down remarkably the decay of the slowly disappearing electrons, whereas the decay of the fast disappearing ones was not affected. It is indicated that the latter electrons are intrinsic to the nature of the 3-methylpentane glass, being bound in shallow traps, and their decay is caused by the migration of the electrons themselves. The former electrons are trapped deeply in anomalous sites in the glass such as impurity sites. Their decay is caused mainly by the migration of positive charges.