OH + Isoprene: A Direct Dynamics Study

The products and mechanisms active in the isoprene + OH reaction were investigated using the direct dynamics method. High energies were used in order to identify every possible reaction channel. The trajectories were classified as dissociative and nondissociative, depending on whether fragmentation occurred during the 4 ps time window of the simulations. The nondissociative trajectories were further classified as radical additions, rearrangements, and cyclizations. The most dominant category was the addition of OH to the carbons of isoprene to form adducts. Some adducts react further by isomerization and cyclization. The dissociative trajectories were classified as hydrogen abstractions, substitutions, and eliminations. Among these, the dominant category was direct hydrogen abstraction to produce H 2 O and a free radical. At higher energies, more reaction was observed. In simulations at 300K , the only reaction category observed was OH addition to the double bonds in isoprene to form adducts.