Stationary points of the potential surface for the reaction F-+CH3Cl->FCH3+Cl-: Results of large-scale coupled cluster calculations

Stationary points of the potential surface for the S(N)2 reaction F-+CH3Cl-->FCH3+Cl- have been investigated by large-scale CCSD(T) calculations. The ion-dipole complexes in the reactant and product channels have well depths of 15.8 and 9.6 kcal mol(-1), respectively, and are separated by a small barrier of 3.3 +/- 0.3 kcal mol(-1). The molar reaction enthalpy at 298 K is obtained to be -31.5 kcal mol(-1).