Reactions of trapped electrons in organic glasses

In this Letter we analyze electron scavenging in glasses and make a comparative study of the direct reaction of electrons with scavengers vs. a multiple-step electron migration over the traps prior to capture. For the direct reaction we obtain exact expressions for the survival probability and approximate decay laws, valid for low scavenger concentrations and long times. The electron migration is modeled in the continuous time random walk (CTRW) formalism, by obtaining stepping time distributions from direct transfer expressions. We conclude that the direct reaction mechanism provides a more suitable description of experimental data than the multiple-step process.