Chemical Physics Letters vol:341 issue:1-2 pages:93-98
The pulsed-laser-photolysis technique was used to determine the rate constant of the gas-phase reaction between the hydroxyl radical (OH) and HNO3 for the first time under conditions of high relative humidity at (295 +/- 3) K. The value obtained, at a total pressure of 200 Torr N-2, was 1.64(-0.20)(+0.11) x 10(-13) cm(3) s(-1) (error limits include assessment of systematic errors), in excellent agreement with the most recent determinations [J. Phys. Chem. 103 (1999) 3031], and was invariant with relative humidity up to 0.50. The shape of the HNO3 absorption bands between 210 and 350 nm also showed negligible Variation with relative humidity. (C) 2001 Elsevier Science B.V. All rights reserved.