OH(A-X) fluorescence from photodissociative excitation of HO2 at 157.5 nm

The OH(A-X) fluorescence from photodissociative excitation of HO2 by F2 laser photons (157.5 nm) was observed and compared with the OH fluorescence spectra of H2O2 and the O2+CH3OH mixture. The rotational population distributions of OH(A) were obtained from the fluorescence spectra. The most populated levels are J = 4 for photodissociative excitation of HO2, J = 20 for H2O2, and J = 21 for the O2+CH3OH mixture. The fluorescence from the gas mixture is attributed to the O + H recombination for which the atoms are produced from photodissociation of parent molecules.