Esr and cidep studies of the photooxidation of phenols in single crystals and in solutions

Abstract
Photooxidation of single crystals of 2,6-di-tert-butyl-4-methylphenol and 2,6-di-tert-butylphenol, respectively, led to localized pair-wise trapping of triplet phenoxyl radical pairs. Electron ejection is not implicated in the primary photooxidation of phenols in single crystals, but in liquid solutions time-resolved CIDEP observations for the 2,4,6-tritert-butylphenol in hexaftuorobenzene suggest an initial formation of a phenol radical cation from the photoexcited triplet state.