Reaction of benzene with atomic carbon: Pathways to fulvenallene and the fulvenallenyl radical in extraterrestrial atmospheres and the interstellar medium

Abstract

The reaction of benzene with ground-state atomic carbon, C(3P), has been investigated using the G3X-K composite quantum chemical method. A suite of novel energetically favorable pathways that lead to previously unconsidered products are identified. Reaction is initiated by barrierless C atom cycloaddition to benzene on the triplet surface, producing a vibrationally excited [C7H6]* adduct that can dissociate to the cycloheptatrienyl radical (+ H) via a relatively loose transition state 4.4 kcal mol-1 below the reactant energies. This study also identifies that this reaction adduct can isomerize to generate five-membered ring intermediates that can further dissociate to the global C7H5 minima,..