State-to-State Mode Specificity in F + CHD3 → HF/DF + CD3/CHD2 Reaction.

The F + CHD3 → HF/DF + CD3/CHD2 reaction is studied using a state-to-state quasi-classical trajectory method on a recently developed ab initio based full-dimensional potential energy surface. Consistent with sudden vector projection model predictions, the HF/DF products are highly excited in both vibrational and rotational modes, while the CD3/CHD2 product internal excitation is mostly in the umbrella/out-of-plane mode. Furthermore, the C-H stretching vibration in the CHD3 reactant is found to behave as an active mode for the HF + CD3 channel, leading to additional excitation in the HF product but having almost no impact on CD3 vibrational state distributions. On the other hand, this mode acts as a spectator for the DF + CHD2 channel, exerting little influence on the DF and other CHD2 vibrational modes except an extra quantum excitation in the C-H stretching mode. The calculated vibrational state resolved differential cross sections are in good agreement with available experimental results at Ec = 9.00 kcal/mol.