Influence of paramagnetic additives on the magnetic effect in the recombination of phenoxyl and semiquinone radicals in micelles

Magnetic and spin effects in radical reactions have recently been attracting increasing attention. An especially strong magnetic field effect has been observed in the recombination of radicals in a radical pair generated in the triplet state within the microscopically closed space within a micelle. This effect is a result of hindrance to T +/- ..-->.. T/sub 0/, S transitions in the radical pair due to Zeeman splitting of the triplet sub-levels. In a sufficiently strong magnetic field, the rate of recombination of radicals in a pair formed in T +/- states is a function of the rate of paramagnetic relaxation due to anisotropic magnetic interactions. This rate may be enhanced due to the introduction of paramagnetic additives such as lanthanide ions. In the present work, they studied the influence of oxygen, stable nitroxyl radicals and paramagnetic a complex on the magnetic effect in the recombination of the radical pairs formed in the quenching of the triplet state of 2,6-diphenyl-1,4-benzoquinone by 4-phenylphenol in a micellar aqueous solution of sodium dodecylsulfate.