Solvation spectra. Part 15.—Dependence of e.s.r. spectra of monoprotonated semiquinones upon solvent

Abstract

The electron spin resonance hyperfine splitting constants of the ring and hydroxylic protons of monoprotonated p-benzosemiquinone are reported for solutions of this radical in several solvents. The results indicate that previously reported variations in the hyperfine splitting constant of the hydroxylic protons of monoprotonated durosemiquinone may be attributed to steric interaction between the adjacent hydroxyl and methyl groups.