Absolute rate constants, reactive cross-sections and isotopic branching ratio for the reaction of O(1D) with HD

✍ Scribed by T. Laurent; P.D. Naik; H.-R. Volpp; J. Wolfrum; T. Arusi-Parpar; I. Bar; S. Rosenwaks

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 512 KB
• Volume: 236
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(95)00213-n

✦ Synopsis

Using the laser photolysis vacuum-UV laser-induced fluorescence 'pump-and-probe' technique, Doppler profiles of H and D atoms from the reaction O(1D) + HD were measured under single-collision conditions, O(aD) atoms were generated by laser photolysis of N20 at 193 nm. With a calibration method using HC1 photolysis as a source of well defined H atom concentrations the following absolute rate constants k and absolute reactive cross-sections or R have been determined: k = (1.3 _+ 0.3) × 10 -l° cm3s -x molec i and O'R(0.14 eV) = (4.0 ___ 0.9) ~2 for the reaction channel O(1D) + HD ~ OD + H, and k = (1.0 _+ 0.3) × 10 10 cm 3 s-1 molec-1 and O'R(0.14 eV) = (3.0 _+ 0.7) ~2 for the reaction channel O(aD) + HD OH + D. The isotopic branching ratio for the reaction O(1D) + HD was measured directly to be FH/D = 1.35 _+ 0.20. In addition, from the measured H and D atom Doppler profiles the fraction fT of the available energy released as translational energy was determined for the individual product channels to be fT(OD + H) = 0.41 _+ 0.07 and fT(OH + D) = 0.32 +_ 0.05.