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Indexed by:Journal Papers

Date of Publication:2015-12-17

Journal:JOURNAL OF PHYSICAL CHEMISTRY A

Included Journals:SCIE、EI、PubMed、Scopus

Volume:119

Issue:50,SI

Page Number:12284-12290

ISSN No.:1089-5639

Abstract:The reaction of fluorine atom with vibrationally excited H-2 at v = 1 has been studied using a high resolution crossed Molecular beam apparatus at collision energies of 0.52 and 0.90 kcal/mol. Product HF rotational state-resolved differential cross sections (DCSs) were measured at v' = 2, 3, 4 levels. The product angular distributions are predominantly backward scattered except for a small forward signal of HF(v' = 4) at 0.90 kcal/mol. At the collision energy of 0.52 kcal/mol, the forward scattering peak of the HF(v' = 2) product, which arises in F + H-2(v = 0) reaction from the Feshbach resonances, disappears in F + H-2(v = 1) reaction. Oscillatory structures do not appear in the backward direction of the scattering as the collision energy increases from 0.4 to 2.0 kcal/mol, indicating there are no:explicit reaction resonances in the F + H-2(v = 1, j = 0) > HF + H reaction in the studied energy range. Quantum dynamics calculations on a highly accurate potential energy surface are in good agreement with the experimental results and reveal that the reaction occurs via likely a direct abstraction mechanism, not via long-lived reactive resonances.