A shock tube study of the OH + OH → H 2 O + O reaction

The rate coefficient for the reactionhas been determined in mixtures of nitric acid (HNO 3 ) and argon in incident shock wave experiments. Quantitative OH time‐histories were obtained by cw narrow‐linewidth uv laser absorption of the R 1 (5) line of the A 2 σ + ← X 2 Π i (0,0) transition at 32606.56 cm −1 (vacuum). The experiments were conducted over the temperature range 1050–2380 K and the pressure range 0.18–0.60 atm. The second‐order rate coefficient was determined to be\documentclass{article}\pagestyle{empty}\begin{document}$$ k_1 = 9.40 \times 10^{- 5} T^{4.77} \exp \left({{{+ 4570} \mathord{\left/ {\vphantom {{+ 4570} {T\left[{\rm K} \right]}}} \right. \kern-\nulldelimiterspace} {T\left[{\rm K} \right]}}} \right)\left[{{\rm cm}^{\rm 3} {\rm mol}^{- 1} {\rm s}^{- 1}} \right] $$\end{document}with overall uncertainties of +11%, −16% at high temperatures and +25%, −22% at low temperatures. By incorporating data from previous investigations in the temperature range 298–578 K, the following expression is determined for the temperature range 298–2380 K\documentclass{article}\pagestyle{empty}\begin{document}$$ k_1 = 3.57 \times 10^4 T^{2.40} \exp \left({{{+ 1063} \mathord{\left/ {\vphantom {{+ 1063} {T\left[{\rm K} \right]}}} \right. \kern-\nulldelimiterspace} {T\left[{\rm K} \right]}}} \right)\left[{{\rm cm}^{\rm 3} {\rm mol}^{- 1} {\rm s}^{- 1}} \right]. $$\end{document}© 1994 John Wiley & Sons, Inc.