Radical cations in irradiated solid n-alkanes and polyethylene

The method of time-resolved magnetic field effect (TR MFE) in recombination fluorescence of spin-correlated radical ion pairs has been used to detect and identify radical cations generated at early stages after the pulse irradiation of polyethylene and tricosane. From analysis of TR MFE curves, the widths of unresolved EPR spectra of radical cations have been determined, and their g factors have been evaluated. The results have demonstrated that, as distinct from n-alkanes, primary radical cations in polyethylene are localized on chemical defects of the polymer chain in a time of about 1 ns or less.