A pulse radiolysis study of electron tunneling in an 8 M NaOH glass between 4 and 100 K

摘要

Pulse radiolysis experiments have been performed in an 8 M NaOH glass between 4 and 100 K and in the time range 10minus;6to 10 s. The spur radius was estimated from the decay of the trapped electrons on the red side of the absorption maximum. The spur radius was about 4 nm at 80 K and increased to about 6 nm at 10 K. We studied the decay of trapped electrons in the presence of the following electron scavengers: CrO2minus;4, Fe(CN)3minus;6, and NOminus;2. No temperature dependence was found between 10 and 100 K. To explain the results distancehyphen;dependent and/or timehyphen;dependent Franckndash;Condon factors have been introduced. We show that in the time range studied it is not possible to distinguish between direct tunneling and traphyphen;tohyphen;trap tunneling. Dry electron scavenging efficiencies and encounter pair formation are expressed inS37. For CrO2minus;4, Fe(CN)3minus;6, and NOminus;2we found thatS37was 45, 130, and 300 M, respectively.