A photoconductivity study of trapped ionic species in gamma-irradiated ethylcyclohexane glass at 77 K

A photoconductivity study has been made of trapped ionic species in γ-irradiated ethylcyclohexane glass at 77K. The photocurrent peak initially increases with an increase in the dose, reaches a maximum, and then decreases with a further increase in the dose. The experimental results indicate that the photocurrent vs. dose curve is probably affected by the radiolysis products. The photocurrents of γ-irradiated ethylcyclohexane-cyclopentane and 3-methylpentane glasses were also measured in the presence of biphenyl. It has been observed that electrons can be transferred almost reversibly between the biphenyl molecules and solvent traps. An analysis of the experimental data shows that only a very small fraction of the trapped electrons are responsible for the observed photoconductivity. A procedure is developed for estimating the lifetime of mobile electrons in glassy matrices. (auth.)