Communication: Non-adiabatic coupling and resonances in the F + H2 reaction at low energies

Quantum reactive scattering calculations on accurate potential energy surfaces predict that at energies below similar to 5 meV, the reaction of F atoms with H-2 is dominated by the Born-Oppenheimer (BO) forbidden reaction of the spin-orbit excited F(P-2(1/2)) atom. This non-BO dominance is amplified by low-energy resonances corresponding to quasi-bound states of the HF(v = 3, j = 3) + H product channel. Neglect of non-adiabatic coupling between the electronic states of the F atom leads to a qualitatively incorrect picture of the reaction dynamics at low energy. (C) 2011 American Institute of Physics. [doi:10.1063/1.3603453]