Infrared Chemiluminescence and Laser-Induced Fluorescence Studies of Energy Disposal by Reactions of F and Cl Atoms with H2S (D2S), H2Se, H2O (D2O), and CH3OH

Article abstract of DOI:10.1021/j100402a039

The vibrational energy disposal to HF (DF), HCl (DCl), SH (SD), and CH3O and relative product formation rate constants were measured for the title reactions.The experiments were done in a fast-flow reactor with infrared emission and laser-induced fluorescence to observe nascent product state distributions for the diatomic hydride products.The CH3O vibrational and HF (DF) rotational distributions are partially relaxed, but the nascent distributions for these cases were estimated.Laser-induced fluorescence measurements showed that the SH, SD, and CH3O fragments received only 0.02-0.03 of the available energy.The v(HX)> values for group VI (group 16) hydrides, 0.45 (F + H2S), 0.44 (F + D2S), 0.48 (F + H2Se), 0.42 (F + D2O), 0.41 (Cl + H2Se), and 0.37 (Cl + D2S), are similar but distinctly smaller than for F and Cl atom reactions with group IV and VII (group 14 and 17) hydrides.The R(HX)> values, 0.18 (F + H2S), 0.19 (F + H2Se), and ca.0.14 (F + D2S), are typical for H-abstraction reactions with similar cross sections.The F + H2O/D2O systems were used to characterize the extent of secondary reactions in the fast-flow reactor.For high reagent concentrations and longer reaction times, S2 was observed in the F/Cl + H2S systems by LIF.