Journal of Physical Chemistry A, Vol.103, No.39, 7800-7810, 1999
Reaction of OH radical with C2H3Cl: Rate constant and reaction pathway analysis
There are two different carbon sites in C2H3Cl where OH addition or abstraction reactions can occur, alpha and beta to the Cl atom, with several dissociation and isomerization products of each addition adduct. Thirteen elementary reactions and 18 species are included in the analysis of this reaction system. Thermochemical kinetic parameters are developed for each elementary reaction process. Chemical activation kinetic analysis with multifrequency QRRK theory for k(E) and master equation for falloff an used to estimate overall rate constants as functions of temperature and pressure. Thermodynamic parameters, including Delta H(f)degrees(298), S degrees(298), and C(p)degrees(T) (300 less than or equal to T/K less than or equal to 1500), of stable species are from the literature when available or estimated by the group additivity method. Values for CHClOH(C) over dot H-2, are determined by density functional calculation and isodesmic reactions. Results are compared with the experimental data. Rate constants (300 similar to 2000 K, in cm(3) mol(-1) s(-1). E-a in cal/mol) for the important addition and abstraction channels at 760 Torr are as follows: k = 1.22 x 10(84)T(-25.5) exp(-15000/RT) for C2H3Cl + OH --> CHClOH(C) over dot H-2; k = 1.77 x 10(40)T(-9.08) exp(-7240/RT) for C2H3Cl + OH --> (C) over dot HClCH2OH; k = 9.72 x 10(6)T(2) exp(-3800/RT) for C2H3Cl + OH --> CH2=(C) over dot Cl + H2O; k = 1.69 x 10(7)T(2) exp(-4390/RT) for C2H3Cl + OH --> (C) over dot H=CHCl + H2O.