Hg(63P1) photosensitization of 3,3-dimethylbut-1-ene. Reactions of vibrationally excited triplet 3,3-dimethylbut-1-ene and the 2,2-dimethylbuta-1,3-diyl biradical

Abstract

Hg(6³P₁) photosensitization of 3,3-dimethylbut-1-ene in the gas phase at 24±1°C has been used to investigate the reactions of both vibrationally excited triplet 3,3-dimethylbut-1-ene and triplet 2,2-dimethylbuta-1,3-diyl biradicals. From a study of the pressure dependence of the mercury photosensitization product quantum yields, rate constants for the decomposition, isomerization and intersystem crossing of these two excited intermediates have been deduced. Where appropriate the experimental rate constants are compared to those calculated using RRKM theory, thereby enabling rough estimates of the critical energies for these processes to be estimated.