Bond Dissociation Energies of CF3-X Bonds (X = C, O, N, S, Br): Ab Initio Molecular Orbital Calculation and Application to Evaluation of Fire Suppression Ability

The C−X (X = C, O, N, S, Br) bond dissociation enthalpies (BDEs) of perfluoroalkanes, perfluoroethers, perfluorotrimethylamine, perfluorodimethyl sulfide, and trifluoromethyl bromide were evaluated by the G2, G2MP2, and G2MS methods. Perfluoroethers had high BDEs of the C−O bond because of the strong negative hyperconjugation between the CF 3 group and lone pair orbitals of oxygen. The BDEs of CF 3 −X bonds could be used as an index of the fire suppression ability.