Electron tunnelling in glassy media. γ-Radiolysis investigation of electron scavenging in methanol, 2-methyltetrahydrofuran and 10 mol dm–3 hydroxide glasses at 77 K

Abstract

The efficiency of electron scavenging by a range of solute molecules in methanol, 2-methyltetrahydrofuran (MTHF) and 10 mol dm^–3 hydroxide glasses has been investigated by γ-radiolysis at 77 K using spectrophotometric detection. The data have been analyzed using the recent theory of Dainton, Pilling and Rice, and a satisfactory fit found. The trap depths for the three systems are estimated to be 1.7 eV (methanol), 1.0 eV (MTHF) and 0.95 eV (aq. hydroxide). A wide variation in the scavenging efficiency is tentatively ascribed to the differing geometries of the scavenger molecules. For MTHF and 10 mol dm^–3 hydroxide glasses, the efficiency of scavenging is independent of wavelength, suggesting that the width of the electron spectrum is not due to a range of trap depths.