Saturation studies of the electron spin resonance due to trapped electrons in gamma-irradiated and photo-ionized organic glasses

Abstract

Relaxation times for trapped electrons in organic glasses at 77°K have been determined from the power saturation characteristics of the electron spin resonance. The spin-lattice relaxation time T₁ is longer than 10^–3 sec, and the spin-spin relaxation time T₂ decreases with γ-irradiation dose. The saturation behaviour of a photo-ionized glass is similar to that of the corresponding γ-irradiated glass when the comparison is made at nearly the same bulk concentration of trapped electrons. Evidence for a non-uniform distribution of paramagnetic species in these irradiated glasses is critically examined, and attention is directed to difficulties of interpretation.