Oxygen-assisted enhancement of H atom UV-photogeneration from hydrocarbons in van der Waals complexes RH–O₂

The strong enhancement of H-atom UV-photogeneration is revealed in van der Waals complexes of unsaturated hydrocarbons RH (RH=ethylene C₂H₄, propylene C₃H₆, butadiene C₄H₆, butene–2 C₄H₈) with oxygen RH–O₂ as compared with the ‘free’ RH molecules. The results obtained indicate enhancement of H atom yield to be due to one-quantum photoprocess ¹RH–³O₂ + hν → ³RH^∗  + ³O₂(¹O₂) providing triplet RH molecules with excitation level sufficient for dissociation.