Collisions of O(D-1) with HCl, Cl-2, and COCl2: Total quenching, channel specific rate constants, and yields of Cl(P-2(1/2))

The method of time-resolved laser magnetic resonance was used to monitor Cl atoms produced by the reactions of O(D-1) with HCl, Cl-2, and COCl2 at room temperature. For these reactions, the measured relative quantum yields of spin-orbit excited atoms are [Cl(P-2(1/2)]/([Cl(P-2(1/2))] + [Cl(P-2(3/2))]) = (0.10 +/- 0.04), < 0.05, < 0.10, respectively. The rate constants for total removal of O(D-1) by HCl, Cl-2, and COCl2 have been determined to be (1.5 +/- 0.3), (2.5 +/- 0.5) and (2.6 +/- 0.5), respectively. The reactive rate constants have been determined to be k(2) = (0.94 +/- 0.2), k(4) = (1.9 +/- 0.3), and k(5a) + 2k(5b) = (2.1 +/- 0.27); here k(2), k(4), k(5a), and k(5b) are rate constants of O(D-1) + HCl --> OH + Cl (2), O(D-1) + Cl-2 --> ClO + Cl (4), and O(D-1) + COCl2 --> CO + ClO + Cl (5a), CO2 + 2Cl (5b), respectively. The rate constants are in units of 10(-10) cm(3)/molecule . s, quoted errors are 2 sigma. (C) 1997 American Institute of Physics.