Trapped Electrons in γ-Irradiated 3-Methylpentane at −196°

The yield of solvent-trapped electrons in γ-irradiated 3-methylpentane at −196° was 0.75 per 100 eV when measured within a few seconds, and diminished to ∼0.6 after 3 min. The quantum yield for bleaching at 950 mμ decreased from 0.8 toward zero with progressive bleaching. Addition of 0.05% biphenyl maintained the quantum yield at >0.8 until more than 90% of the solvent trapped electrons had bleached. The initial quantum yield at λ>1.7μ was ∼0.01, both with and without added biphenyl. There is qualitative correlation between photobleaching and the rate of spontaneous decay.