Czako and coworkers developed 20 analytical PESs for the F -+ CH3I SN2 and proton-abstraction reactions with the energies computed at the levels of HF, MP2, several density function theories(DFT), coupled-cluster based methods associated with the basis sets, AVDZ and AVTZ. QCTs were carried out on these PESs to reveal the influence of the electronic structure levels on the dynamic results. 108