E.S.R. studies of semiquinones

Abstract

Electron spin resonance spectra are reported for durosemiquinone, 2,3-, 2,5-, and 2,6-dimethyl-p-benzosemiquinone dissolved in 1,2-dimethoxyethane and in t-pentanol; these radicals are present both as free ions and as ion-pairs with lithium, sodium, potassium, and caesium ions. Molecular orbital parameters characterizing the various systems are evaluated as are activation energies for the intramolecular migration of the cation which occurs within several of the ion-pairs.