Reactions of small carbon-bearing radicals with unsaturated hydrocarbons: Product detection and low temperature kinetics
We report on results from two experimental techniques concerned with the reactions of small carbon based radicals (CN and CH) with unsaturated hydrocarbons. First, low temperature (100-300K) kinetic studies using a pulse Laval nozzle technique probe the reactions of the CN radical with benzene and toluene. The CN + benzene is found to be a fast, barrierless reaction. But in the case of toluene, two reaction pathways are in competition, one of which back dissociates to the reactants. The implications for the atmosphere of Titan are discussed. Product detection studies undertaken at the Advanced Light Source (ALS) using synchrotron coupled multiplexed mass spectrometry comprise the other component of this undertaking. The CH + C2H2 reaction is investigated by detecting the products and furthermore the reaction pathways are probed using isomer resolved mass spectrometry and isotopic labelling.