CN radical reactions with hydrogen cyanide and cyanogen - Comparison of theory and experiment

The method of laser photolysis/laser-induced fluorescence is used to obtain absolute rate constants for CN radical reactions with HCN and C2N2. The rate constants were found to be temperature-dependent in the range 300-740 K and pressure independent in the range 100-600 Torr. Rice-Remsperger-Kassel-Marcus theory for both reactions employing the transition state parameters obtained by the BAC-MP4 method are made. These calculations yielded reasonable results for the CN + HCN reaction, predicting both the temperature dependence and pressure independence. No pressure effect was observed in the pressure range 100-1000 Torr at temperatures below 900 K, confirming the experimental results.