Table 6: Enthalpies of activation and reaction at 0 K (in kcal/mol) for addition reactions.

This workWu et al.
M08-SO/MG3S CCSD(T)-F12/ jun-cc-pVTZ M06-2X G3(MP2)-RAD CBS
with with with with

Enthalpy of activation
o-add (R5)-1.68-1.70-0.92-0.940.140.501.46
m-add (R6)0.380.370.570.562.222.22-0.05
p-add (R7)-0.17-0.190.280.261.411.530.12
ipso-add (R8)-0.86-0.87-0.43-0.441.000.861.48
Enthalpy of reaction
o-add (R5)-19.60-19.64-18.48-18.52-18.74-17.66-19.00
m-add (R6)-18.05-18.09-17.28-17.32-17.04-16.40-17.50
p-add (R7)-18.60-18.64-17.44-17.48-17.38-16.37-17.73
ipso-add (R8)-19.26-19.30-19.12-19.16-18.48-18.48-19.62

The ZPEs are obtained by M08-SO/MG3S with scaled frequencies. b M06-2X/6-311++G(2df,2p). c G3(MP2)-RAD//M06-2X/6-311++G(2df,2p). The meaning of “//” is that geometries and frequencies recalculated by the method after the double slash, and single-point energies are calculated by the method before the double slash. d ROCBS-QB3//M06-2X/6-311++G(2df,2p).