An analysis of the cross-combination ratio of the rate constants phi i
n terms of the statistical adiabatic channel model allows to factorize
phi into two contributions: one due to the motion along the reaction
coordinates and another due to the reaction transitional modes. Phi fo
r the CH3/CCl3, CH3/C2H3, CH3/C3H5, CH3/C2H5 and C2H5/C3H5 radical pai
rs were calculated.