Sensitivity of the product vibrational distribution of the F + H2 reaction to the T5A potential energy surface

Sensitivities for the transition probability of the F + H2 (v = 0, j = 0) → HF (v′) + H reaction are calculated for total angular momentum J = 0 to determine how the T5A potential energy surface (PES) can be modified to correct its theoretical product vibrational branching ratio. Several modifications of the T5A PES are suggested and compared with the actual PES modifications that have led to the newer 5SEC and 6SEC surfaces. It is seen that the 6SEC surface is substantially better than 5SEC which, in turn, is better than T5A with respect to the suggested PES modifications. The match is not perfect and one can contemplate using the sensitivities for other PES refinements that would lead to even better agreement with experiment.