Electron capture in .gamma.-irradiated 2-methyltetrahydrofuran glasses containing two solutes at 77 K

Abstract

Solute-anion yields in -irradiated 2-methyltetrahydrofuran glasses containing two solutes were measured at 77 K. For solute pairs of p-benzoquinone (BQ)-biphenyl, BQ-pyrene, 1,4-naphthoquinone (NQ)-biphenyl, and pyrene-biphenyl, the results are summarized as follows.(1) The yield of the anion of the left-hand solute (Si) in each pair is little dependent upon the concentration of the other solute (S2). ( 2) The logarithm of the S2-anion yield is approximately linear in Si concentration. The electron affinity of the first solute is larger than that of the second. The results are consistent with a scheme that an electron once trapped in a matrix tunnels to either SI or S2 to form solute anions and an electron also tunnels from S2" to SI. The yield of the anion of each solute in a BQ-NQ pair was found to depend on the concentration of the counterpart, in contrast with the results for the above solute pairs. The results for this pair can be explained in terms of a competitive capture scheme which does not include the tunneling from S2~to SI.

Electronic Structure and Optical Properties of Charged Oligofluorenes Studied by VIS/NIR Spectroscopy and Time-Dependent Density Functional Theory

“…The formation of fluorene radical anions (DHF n •- ) in γ-irradiated 2-methyltetrahydrofuran (MTHF) is attributed to attachment of electrons to oligofluorene molecules, analogous to experiments performed by Kira et al The optical absorption spectra of DHF n radical anions in solid matrix are similar to those measured in solution, see Figure and Table .…”