The vibrational excitation of hydrogen fluoride behind incident shock waves

The vibrational excitation of HF occurring behind incident shock waves has been studied in the temperature range of 1400°K to 4100°K. The extent of excitation was determined as a function of time by continuously monitoring the emission intensity from the 1–0 band of HF centered at 2.5 μ. The data were interpreted in terms of the process\documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm HF}(0) + {\rm M = HF(1)} + {\rm M} $$\end{document}and gave a value of\documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm (}\tau \rho {\rm)}\begin{array}{*{20}c} {{\rm - 1}} \\ {{\rm HF}} \\ \end{array}{\rm = 10}^{{\rm 9}{\rm .2} \pm 0.1} \exp \left({\frac{{- 64 \pm 4}}{{T^{1/3}}}} \right)atm^{- 1} \sec ^{- 1} $$\end{document}for M = HF. The corresponding result for (τ p ) −1 Ar was found to be insignificant in comparison to this result. Data were also obtained for the effect of F atoms upon the relaxation rate, i.e., it was found that\documentclass{article}\pagestyle{empty}\begin{document}$$ {{\left( {\tau p} \right)_{{\rm HP}} } \mathord{\left/ {\vphantom {{\left( {\tau p} \right)_{{\rm HP}} } {\left( {\tau p} \right)_{\rm F} \sim 18 \pm 1}}} \right. \kern-\nulldelimiterspace} {\left( {\tau p} \right)_{\rm F} \sim 18 \pm 1}} $$\end{document}