Table 3.

Comparison of the experimental (exp.) and theoretical (calc.) values of the enthalpy of formation of the reactants CH₃X and products CH₂X, (X = F, Cl and Br) obtained at the G2 level

Molecular	(calc.)	(exp.) a)
system	(kJ mol−1)	(kJ mol−1)
CH3F	−237.7	−238 ± 8
CH3Cl	−81.4	−81.9 ± 0.6
CH3Br	−32.0	−37.7 ± 1.5
CH2F	−28.1	−32 ± 8
CH2Cl	120.4	117.3 ± 3.1
CH2Br	174.9	169 ± 4

^a)from ref. 12