Evidence for the formation of vibrationally excited triplet 1,3-biradicals in the Hg 3P1 photosensitized decomposition of cis- and trans-3,4-dimethyl-Δ1-pyrazoline
Abstract
Mercury photosensitized decomposition of cis- and trans-3,4-dimethyl-Δ1-pyrazoline vapour yields vibrationally excited triplet biradical intermediates which undergo pressure-dependent isomerizations to form olefins or cyclization to dimethylcyclopropanes.