Kinetics for the reaction of phenyl radical with phenylacetylene and styrene

The kinetics for the reactions of C6H5 with phenylacetylene and styrene have been measured by CRDS in the temperature range 297–409 K under an Ar pressure of 3.6 Torr. The total rate constants can be given by the following Arrhenius expressions (in units of cm3 mol−1 s−1): k1(C6H5 + C6H5C2H) = 1013.0±0.1exp [−(2430 ± 150)/RT] and k2(C6H5 + C6H5C2H3) = 1013.3±0.1 exp [−(2570 ± 180)/T]. Additional DFT and MP2 calculations have been carried out to assist our interpretation of the measured kinetic data. The addition of C6H5 to the terminal CHx (x = 1 or 2) sites is predicted to be the dominant channel for both reactions. The calculated bimolecular rate constants are in reasonable agreement with experimental values for the temperature range studied.