title: Negative collision energy dependence of Br formation in the OH + HBr reaction.
abstract: The reaction between HBr and OH leading to H(2)O and Br in its ground state is studied by means of a crossed molecular beam experiment for a collision energy varying from 0.05 to 0.26 eV, the initial OH being selected in the state |JOmega> = |3/2 3/2> by an electrostatic hexapole field. The reaction cross-section is found to decrease with increasing collision energy. This negative dependence suggests that there is no barrier on the potential energy surface for the formation pathway considered. The experimental results are compared with the previously reported quantum scattering calculations of Clary et al. (D. C. Clary, G. Nyman and R. Hernandez, J. Phys. Chem., 1994, 101, 3704), and briefly discussed in the light of skewed potential energy surfaces associated with heavy-light-heavy type reactions.
authors.affiliation: Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka, 560-0043, Japan.
authors.forename: Dock-Chil
authors.initials: DC
authors.lastname: Che
authors.forename: Takashi
authors.initials: T
authors.lastname: Matsuo
authors.forename: Yuya
authors.initials: Y
authors.lastname: Yano
authors.forename: Laurent
authors.initials: L
authors.lastname: Bonnet
authors.forename: Toshio
authors.initials: T
authors.lastname: Kasai
mesh_terms: D001966:Bromine / Q000737:chemistry*; D018054:Hydrobromic Acid / Q000737:chemistry*; D017665:Hydroxyl Radical / Q000737:chemistry*; D011789:Quantum Theory; D013816:Thermodynamics; D014867:Water / Q000737:chemistry
chemical_list: D014867:Water; D017665:Hydroxyl Radical; D018054:Hydrobromic Acid; D001966:Bromine