State-to-state dynamics of atom+polyatom reactions. III. The H+CDCl3→HD(v′,j′)+CCl3 reaction

We report measurement of the HD product quantum state distributions for the H+CDCl3→HD(v′,j′)+CCl3 reaction at a collision energy of 1.6 eV using coherent anti-Stokes–Raman scattering (CARS). We determine relative HD(v′,j′) population distributions and absolute partial and total cross sections. The total cross section is 0.55±0.10 Å2. HD products are observed in v′=0, 1, and 2, with 7% of the available energy in HD product vibration. As with previous light+light–heavy→light–light+heavy reactions, the total energy in rotation, 15%, is also small. HD formed in v′=1 and 2 have greater fractions of rotational energy in relation to the energy available to them than HD in v′=0, with gr=〈Erot〉/(Etot−Evib)=0.15, 0.20, and 0.19 for v′=0, 1, and 2, respectively. Linear surprisal analysis shows that the excited vibrational levels have less bias against rotational excitation than the ground state level, respectively, if the CCl3 fragment is regarded as structureless. Comparison with previous state-to-state dynamics results of kinematically similar H+HX→H2+X (X=Cl, Br, I) and H+HR/DR→H2/HD+R (R=CD3, C2H5, C3H7) reactions indicate that the positive (v′,j′) correlation may be intrinsic to polyatomic hydrogen atom abstraction reactions.