High‐temperature determination of the rate coefficient for the reaction H 2 + CN → H + HCN

The rate coefficient of the reaction\documentclass{article}\pagestyle{empty}\begin{document}$$(2){\rm H}_2 {\rm CN} \to {\rm H} + {\rm HCN}$$\end{document}has been determined in the temperature range of 2700–3500 K using a shock tube technique. C 2 N 2 H 2 Ar mixtures were heated behind incident shock waves and the early‐time CN history was monitored using broad‐band absorption spectroscopy. The rate coefficient providing the best fit to the data was\documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm k = (7}{\rm .5}_{ - 2.0}^{{\rm + 2}{\rm .5}} {\rm)} \times {\rm 10}^{{\rm 13}} {\rm cm}^3 /{\rm mol} \cdot {\rm s} $$\end{document}in good agreement with extrapolations of previously published low‐temperature results.