title: Time dependent wave packet and statistical calculations on the H + O(2) reaction.
abstract: The H + O(2)--> OH + O reaction has been theoretically investigated by means of an exact time dependent wave packet method and two statistical approaches: a recently developed statistical quantum model and phase-space theory. The exhaustive analysis of reaction probabilities at a zero total angular momentum would, in principle, reveal the existence of a complex-forming mechanism at low collision energies (E(c) = 1.15 eV), whereas deviations from a statistical behaviour at higher energies may be interpreted as the onset of a direct abstraction pathway which favours the production of highly excited rotational states of the OH fragment in its ground vibrational state. The good description by statistical means of previously measured product rotational distributions and excitation functions seems to support such an interpretation. However the statistical predictions clearly overestimate both existing and present exact quantum mechanical reaction probabilities and total cross sections, thereby precluding to conclude definitely the statistical nature of the collision. The exact time dependent method yields values of the integral cross sections in agreement with results by Goldfield and Meijer, and below the experimental findings.
authors.affiliation: Instituto de Matemáticas y Física Fundamental (CSIC), Serrano 123, 28006 Madrid, Spain.
authors.forename: Pedro
authors.initials: P
authors.lastname: Bargueño
authors.forename: Tomás
authors.initials: T
authors.lastname: González-Lezana
authors.forename: Pascal
authors.initials: P
authors.lastname: Larrégaray
authors.forename: Laurent
authors.initials: L
authors.lastname: Bonnet
authors.forename: Jean
authors.initials: J
authors.lastname: Claude Rayez
mesh_terms: D006859:Hydrogen / Q000737:chemistry*; D008956:Models, Chemical; D015233:Models, Statistical; D010100:Oxygen / Q000737:chemistry*; D011789:Quantum Theory; D013997:Time Factors
chemical_list: D006859:Hydrogen; D010100:Oxygen