Analysis of line-width effects in the electron spin resonance spectra of monoprotonated semiquinones

摘要: Electron spin resonance spectra of monoprotonated p-benzosemiquinone, 2:6-dimethyl-p-benzosemiquinone, and durosemiquinone dissolved in tetrahydrofuran at −70 °C are reported. Under such conditions restricted rotation the hydroxyl group causes ring positions meta to site protonation appear as non-equivalent, though this effect is not observed for durosemiquinone. The p-benzosemiquinone exhibit both anisotropic alternating line-width trends; equations presented which allow separation these two effects determination energy activation between 31 40 kJ/mole. Spectra 2:3- 2:5-dimethyl-p-benzosemiquinones 1:2 dimethoxyethane 20 also