E.S.R. studies of excited states in solution

Abstract

The observation of electron spin polarized spectra from free radicals using flash-photolysis electron spin resonance methods is described. The origins of polarization are summarized and a critical account of their present understanding provided. The phases of the polarized signals carry information on the multiplicity of the radical precursor. Examples are provided from observations of nitrogen heterocyclic radicals of the use of the spectra to obtain such information, and to identify reactive states precisely.