A shock tube study of the OH + OH → H₂O + O reaction

The rate coefficient for the reaction equation image has 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 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 © 1994 John Wiley & Sons, Inc.