title: Iron cation catalyzed reduction of N2O by CO: gas-phase temperature dependent kinetics.
abstract: The ion-molecule reactions Fe(+) + N2O → FeO(+) + N2 and FeO(+) + CO → Fe(+) + CO2, which catalyze the reaction CO + N2O → CO2 + N2, have been studied over the temperature range 120-700 K using a variable temperature selected ion flow tube apparatus. Values of the rate constants for the former two reactions were experimentally derived as k2 (10(-11) cm(3) s(-1)) = 2.0(±0.3) (T/300)(-1.5(±0.2)) + 6.3(±0.9) exp(-515(±77)/T) and k3 (10(-10) cm(3) s(-1)) = 3.1(±0.1) (T/300)(-0.9(±0.1)). Characterizing the energy parameters of the reactions by density functional theory at the B3LYP/TZVP level, the rate constants are modeled, accounting for the intermediate formation of complexes. The reactions are characterized by nonstatistical intrinsic dynamics and rotation-dependent competition between forward and backward fluxes. For Fe(+) + N2O, sextet-quartet switching of the potential energy surfaces is quantified. The rate constant for the clustering reaction FeO(+) + N2O + He → FeO(N2O)(+) + He was also measured, being k4 (10(-27) cm(6) s(-1)) = 1.1(±0.1) (T/300)(-2.5(±0.1)) in the low pressure limit, and analyzed in terms of unimolecular rate theory.
authors.affiliation: Air Force Research Laboratory, Space Vehicles Directorate, Kirtland AFB, NM 87117-5776, USA.
authors.forename: Joshua J
authors.initials: JJ
authors.lastname: Melko
authors.forename: Shaun G
authors.initials: SG
authors.lastname: Ard
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Fournier
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.forename: Nicholas S
authors.initials: NS
authors.lastname: Shuman
authors.forename: Hua
authors.initials: H
authors.lastname: Guo
authors.forename: Jürgen
authors.initials: J
authors.lastname: Troe
authors.forename: Albert A
authors.initials: AA
authors.lastname: Viggiano
mesh_terms: D002248:Carbon Monoxide / Q000737:chemistry*; D002384:Catalysis; D002412:Cations / Q000737:chemistry; D005740:Gases / Q000737:chemistry; D007501:Iron / Q000737:chemistry*; D007700:Kinetics; D009609:Nitrous Oxide / Q000737:chemistry*; D010084:Oxidation-Reduction; D011789:Quantum Theory; D013696:Temperature
chemical_list: D002412:Cations; D005740:Gases; D002248:Carbon Monoxide; D007501:Iron; D009609:Nitrous Oxide