Prediction of methyl C-H bond dissociation energies by density functional theory calculations

Bond dissociation energies [E-D298(R-H)=Delta(r)H(298)degrees] for a series of 15 substituted methane derivatives have been determined by density functional theory (DFT) calculations using the B3LYP functionals on the 6-31G(d,p) basis set, The averages of the experimental data were satisfactorily reproduced with a mean (signed) error of -0.2 kcal mol(-1) (1 cal = 4.184 J) and an rms deviation of 2.2 kcal mol(-1).