On the thermal decomposition of COS

The thermal dissociation of COS was investigated in shock waves with argon as carrier gas. The concentration was varied between 0.05 and 0.5% COS in argon, the total density from 2.5 × 10 −5 mole/cm 3 to 2.5 × 10 −3 mole/cm 3 . Temperatures between 1500°K and 3100°K were applied. For the reaction\documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm COS}\left({^1 \Sigma} \right)\mathop {\longrightarrow}\limits^{K_{\rm 1}} {\rm CO}\left({^1 \Sigma ^ +} \right) + {\rm S}\left({^3 P} \right) $$\end{document}the rate constant was found to be\documentclass{article}\pagestyle{empty}\begin{document}$$ k_{10} \approx 10^{14.2} \exp - \left({\frac{{61000}}{{RT}}} \right) \quad\quad ({\rm cm}^3 {\rm mole}^{- 1} \sec ^{- 1}) $$\end{document}in the low pressure range of the unimolecular reaction and\documentclass{article}\pagestyle{empty}\begin{document}$$ k_{1\infty} \approx 10^{11.6} \exp - \left({\frac{{61000}}{{RT}}} \right) \quad\quad (\sec ^{- 1}) $$\end{document}in the high pressure range.