A direct dynamics study of the F + C ₂ H ₄ → C ₂ H ₃ F + H product energy distributions

Ab initio direct dynamics was used to calculate product energy distributions for the F + C₂H₄ → C₂H₃F + H reaction. A broad product translational energy distribution, similar to that observed experimentally, is found when the trajectories are initialized with a statistical vibrational energy distribution at the exit channel barrier. The trajectories show that, on average, orbital angular momentum is conserved in going from the exit channel barrier to products, and a model which incorporates this dynamical constraint reproduces the ensemble averaged trajectory results.