Scattering, reactive complex formation

Quack M and Troe J 1975 Complex formation in reactive and inelastic scattering statistical adiabatic channel model of unimolecular processes III Ber. Bunsenges. Phys. Chem. 79 170-83... 

The data for non-reactively scattered Y atoms recorded at m/e 89 (not shown) exhibit typical features for impulsive inelastic scattering without appreciable long-lived complex formation.124,127 In the CM reference frame,... 

The symmetry of the Iv(6) distribution about the 6 = 90° plane remains a diagnostic test for complex formation. Moreover, the anisotropy of the / ( ) distribution can be used [44] to determine the partitioning of final angular momentum between L and J and therefore the rotational energy of the diatomic product AB. Unsymmetric scattering of the product about 6 = 90° indicates a direct reactive mechanism, and observations of the preferred direction of recoil provide important evidence concerning the character of the reactive collisions. 

It was pointed out earlier that an important factor in persistent complex formation in reactive scattering systems is the depth of the potential well. In studying the elastic scattering of protons on molecules the Hahn-Meitner Institute group showed that even though one can only deduce average potentials in these molecular systems, such information can have significant applications in interpretation of ion-molecule reactions. 

The existence of such C H O intermediate anion collision complex had previously been suggested by Comer and Schulz [254], who measured the energies of electrons emitted during gas-phase collisions of 0 with C2H4. Further evidence for a complex anion formation and reactive scattering in the gas phase can be seen in the studies of Parkes [255] and Lindinger et al. [256]. 

The Ba -h O2 reaction gives approximately symmetric forward-backward reactive scattering for Et = 2.2 kcal mole" and must proceed via a long-lived complex (also see references mentioned in ref. 28b). Rough vibrational and rotational BaO distributions were obtained by laser fluorescence. Quantitative assignments of populations were thwarted by formation of high J levels, rotational perturbations in the upper state, and lack of detailed... 

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