Quantum mechanical investigation of the reaction CHClBr + O(3P)

The reaction of ground state oxygen atoms with the chlorobromomethyl radical is investigated using high levels of electronic molecular structure theory. The calculations indicate an association–elimination mechanism through the formation of the energy-rich intermediates CHClBrO* and CClBrOH*. The C–Br bond scission and the HBr elimination are the main dissociation pathways of the chlorobromomethoxy radical but Cl release is also shown to be competitive. The hydroxychlorobromomethyl intermediate, CClBrOH, exhibits a much higher stability than CHClBrO with the HBr elimination being the only channel leading to more stable products.