CH stretching excitation steers the F atom to the CD bond in the F + CHD3 reaction.

Quasiclassical trajectories on an ab initio potential energy surface show that a stereodynamical effect steers the F atom away from the stretching-excited CH bond, thereby promoting the DF + CHD(2) product channel of the F + CHD(3)(nu(1) = 1) reaction at low collision energies. This explains the unexpected results of a recent crossed molecular beam experiment.