Electron spin relaxation in polarized secondary radicals

Abstract

The spin-lattice relaxation of some α-diketone radical anions has been studied following their production in a spin-polarized state by reaction of the parent molecule with a polarized primary radical. The latter was the amine radical which results on irradiation of benzophenone in the presence of triethylamine; the relaxation of the polarized benzophenone ketyl produced simultaneously was also studied.

The relaxation of the radical anion from camphorquinone has been investigated in several solvents over wide ranges of viscosity and temperature and has been analysed in terms of contributions from the spin-rotation and g-anisotropy interactions. Different relaxation times were observed at low temperature from optically active d-camphorquinone radical anion in solution in the two optical isomers of 2-octanol.