Velocity-aligned, superthermal O(1D) atoms generated via the photodissociation of N2O have been employed to investigate the stereodynamics of the title reaction. The power of this experimental technique, when coupled with Doppler-resolved, polarized laser-induced fluorescence probing of the reaction products, is demonstrated by reference to the specific reaction channel leading to NO(υ′=0)+NO(υ′=16,17), which is shown to proceed via direct stripping dynamics. Furthermore, the observed product-state selective linear and angular momenta disposals imply that the reaction is stereodynamically constrained to occur via collinear collision geometries.

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The application of polarised, Doppler-resolved laser-induced fluorescence (LIF) probing of the products scattered from photon-induced ' half-collision ' (photodissociation) and 'full-collision ' (bimolecular reaction) processes is developed to include the velocity dependence of their stereodynamics. Fourier-transform inversion procedures are used to derive the products' speed distributions W(v') and vector correlations Blj(v') (a) in the photodissociation of HONO, and (b) in the bimolecular reaction of O('D) with CH, . In the former example, they provide new insight into the stereodynamics of the photodissociation HONO, + hv 4 HO(v = 0, N ) + NO,(%, A) In the latter, together with newly developed LAB --+ CM simulation methods, they provide new insight into the ste reod y n am ics of the react ion O('D) + CH, --+ OH(v = 4, N) + CH,The OH is shown to be generated with its rotational angular momentumj', constrained to lie in a plane directed perpendicular to its centre-of-mass relative velocity, k'.

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The stereodynamics of the reaction Oe D) + CH 4~O H(v~4,N) + CH l at collision energies of -40 kJ mol:', has been probed via Doppler-resolved, polarized laser-induced fluorescence spectroscopy. Velocity-aligned, reagent OeD) atoms were generated under bulb conditions via polarized laser photodissociation of Np. Analysis of the Doppler profiles of nascent OH(v,N) fragments has allowed both scalar and vectorial product correlations to be determined, including differential scattering cross sections and rotational alignments. These imply the operation of a 'delayed' collision mechanism, dominated by the deeply attractive potential energy surface associated with the insertion to form CHpH; the intermediacy of a long-lived complex is excluded, however. Rotational angular momentum in the recoiling OH fragments is preferentially aligned perpendicular to, and azimuthally distributed about, their recoil velocity. The rotational excitation is thereby attributed to bending motion in the c...O···H plane during the reagent collisions. The scalar product pair correlations establish a near-zero translational exoergicity and anticorrelated internal energy distributions in the two reaction products.