Hidden triplet states of aromatic thiols characterized by radiation-chemical sensitization

Because of a complex reaction mechanism the first excited triplet states of aromatic thiols (ArSH) are difficult to identify in real-time UV laser photolysis. In this publication we report on a more promising approach via pulse radiolysis where ArSH(T1) formation is achieved by direct energy transfer from the triplet state of the solvent benzene. Energy levels of a variety of substituted thiophenols have been characterized by sensitization experiments with benzophenone, naphthalene and β-carotene.