Observation of H displacement and H2 elimination channels in the reaction of O(3P) with 1-butene from crossed beams and theoretical studies

We report preliminary combined experimental/theoretical results on O(3P) + 1-butene reaction dynamics with focus on atomic hydrogen displacement and molecular hydrogen elimination channels. Dynamics and relative yield of the ethylvinoxy + H and ethylketene + H2 product channels are characterized in crossed beam experiments. Stationary points and energetics of triplet/singlet C4H8O potential energy surfaces (PESs) are calculated at CCSD(T)/CBS and CASPT2 level. O(3P) attack occurs on both unsaturated C-atoms with preference for the less substituted one leading, among other products, to C2H5CHCHO + H via an exit barrier on the triplet PES, and to C2H5CHCO + H2 via a very high exit barrier on the singlet PES following intersystem crossing.