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Gómez Martín JC, Garraway SA, Plane JMC. Reaction Kinetics of Meteoric Sodium Reservoirs in the Upper Atmosphere. J Phys Chem A 2016; 120:1330-46. [PMID: 25723735 DOI: 10.1021/acs.jpca.5b00622] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The gas-phase reactions of a selection of sodium-containing species with atmospheric constituents, relevant to the chemistry of meteor-ablated Na in the upper atmosphere, were studied in a fast flow tube using multiphoton ionization time-of-flight mass spectrometry. For the first time, unambiguous observations of NaO and NaOH in the gas phase under atmospheric conditions have been achieved. This enabled the direct measurement of the rate constants for the reactions of NaO with H2, H2O, and CO, and of NaOH with CO2, which at 300-310 K were found to be (at 2σ confidence level): k(NaO + H2O) = (2.4 ± 0.6) × 10(-10) cm(3) molecule (-1) s(-1), k(NaO + H2) = (4.9 ± 1.2) × 10(-12) cm(3) molecule (-1) s(-1), k(NaO + CO) = (9 ± 4) × 10(-11) cm(3) molecule (-1) s(-1), and k(NaOH + CO2 + M) = (7.6 ± 1.6) × 10(-29) cm(6) molecule (-2) s(-1) (P = 1-4 Torr). The NaO + H2 reaction was found to make NaOH with a branching ratio ≥ 99%. A combination of quantum chemistry and statistical rate theory calculations are used to interpret the reaction kinetics and extrapolate the atmospherically relevant experimental results to mesospheric temperatures and pressures. The NaO + H2O and NaOH + CO2 reactions act sequentially to provide the major atmospheric sink of meteoric Na and therefore have a significant impact on the underside of the Na layer in the terrestrial mesosphere: the newly determined rate constants shift the modeled peak to about 93 km, i.e., 2 km higher than observed by ground-based lidars. This highlights further uncertainties in the Na chemistry cycle such as the unknown rate constant of the NaOH + H reaction. The fast Na-recycling reaction between NaO and CO and a re-evaluated rate constant of the NaO + CO2 sink should be now considered in chemical models of the Martian Na layer.
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Affiliation(s)
- J C Gómez Martín
- School of Chemistry, University of Leeds , Woodhouse Lane, LS2 9JT, Leeds, U.K
| | - S A Garraway
- School of Chemistry, University of Leeds , Woodhouse Lane, LS2 9JT, Leeds, U.K
| | - J M C Plane
- School of Chemistry, University of Leeds , Woodhouse Lane, LS2 9JT, Leeds, U.K
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Whalley CL, Martín JCG, Wright TG, Plane JMC. A kinetic study of Mg+ and Mg-containing ions reacting with O3, O2, N2, CO2, N2O and H2O: implications for magnesium ion chemistry in the upper atmosphere. Phys Chem Chem Phys 2011; 13:6352-64. [PMID: 21359353 DOI: 10.1039/c0cp02637a] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Reactions between Mg(+) and O(3), O(2), N(2), CO(2) and N(2)O were studied using the pulsed laser photo-dissociation at 193 nm of Mg(C(5)H(7)O(2))(2) vapour, followed by time-resolved laser-induced fluorescence of Mg(+) at 279.6 nm (Mg(+)(3(2)P(3/2)-3(2)S(1/2))). The rate coefficient for the reaction Mg(+) + O(3) is at the Langevin capture rate coefficient and independent of temperature, k(190-340 K) = (1.17 ± 0.19) × 10(-9) cm(3) molecule(-1) s(-1) (1σ error). The reaction MgO(+) + O(3) is also fast, k(295 K) = (8.5 ± 1.5) × 10(-10) cm(3) molecule(-1) s(-1), and produces Mg(+) + 2O(2) with a branching ratio of (0.35 ± 0.21), the major channel forming MgO(2)(+) + O(2). Rate data for Mg(+) recombination reactions yielded the following low-pressure limiting rate coefficients: k(Mg(+) + N(2)) = 2.7 × 10(-31) (T/300 K)(-1.88); k(Mg(+) + O(2)) = 4.1 × 10(-31) (T/300 K)(-1.65); k(Mg(+) + CO(2)) = 7.3 × 10(-30) (T/300 K)(-1.59); k(Mg(+) + N(2)O) = 1.9 × 10(-30) (T/300 K)(-2.51) cm(6) molecule(-2) s(-1), with 1σ errors of ±15%. Reactions involving molecular Mg-containing ions were then studied at 295 K by the pulsed laser ablation of a magnesite target in a fast flow tube, with mass spectrometric detection. Rate coefficients for the following ligand-switching reactions were measured: k(Mg(+)·CO(2) + H(2)O → Mg(+)·H(2)O + CO(2)) = (5.1 ± 0.9) × 10(-11); k(MgO(2)(+) + H(2)O → Mg(+)·H(2)O + O(2)) = (1.9 ± 0.6) × 10(-11); k(Mg(+)·N(2) + O(2)→ Mg(+)·O(2) + N(2)) = (3.5 ± 1.5) × 10(-12) cm(3) molecule(-1) s(-1). Low-pressure limiting rate coefficients were obtained for the following recombination reactions in He: k(MgO(2)(+) + O(2)) = 9.0 × 10(-30) (T/300 K)(-3.80); k(Mg(+)·CO(2) + CO(2)) = 2.3 × 10(-29) (T/300 K)(-5.08); k(Mg(+)·H(2)O + H(2)O) = 3.0 × 10(-28) (T/300 K)(-3.96); k(MgO(2)(+) + N(2)) = 4.7 × 10(-30) (T/300 K)(-3.75); k(MgO(2)(+) + CO(2)) = 6.6 × 10(-29) (T/300 K)(-4.18); k(Mg(+)·H(2)O + O(2)) = 1.2 × 10(-27) (T/300 K)(-4.13) cm(6) molecule(-2) s(-1). The implications of these results for magnesium ion chemistry in the atmosphere are discussed.
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Broadley SL, Vondrak T, Plane JMC. A kinetic study of the reactions of Ca+ ions with O3, O2, N2, CO2 and H2O. Phys Chem Chem Phys 2007; 9:4357-69. [PMID: 17687483 DOI: 10.1039/b704920j] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reactions between Ca(+)(4(2)S(1/2)) and O(3), O(2), N(2), CO(2) and H(2)O were studied using two techniques: the pulsed laser photo-dissociation at 193 nm of an organo-calcium vapour, followed by time-resolved laser-induced fluorescence spectroscopy of Ca(+) at 393.37 nm (Ca(+)(4(2)P(3/2)-4(2)S(1/2))); and the pulsed laser ablation at 532 nm of a calcite target in a fast flow tube, followed by mass spectrometric detection of Ca(+). The rate coefficient for the reaction with O(3) is essentially independent of temperature, k(189-312 K) = (3.9 +/- 1.2) x 10(-10) cm(3) molecule(-1) s(-1), and is about 35% of the Langevin capture frequency. One reason for this is that there is a lack of correlation between the reactant and product potential energy surfaces for near coplanar collisions. The recombination reactions of Ca(+) with O(2), CO(2) and H(2)O were found to be in the fall-off region over the experimental pressure range (1-80 Torr). The data were fitted by RRKM theory combined with quantum calculations on CaO(2)(+), Ca(+).CO(2) and Ca(+).H(2)O, yielding the following results with He as third body when extrapolated from 10(-3)-10(3) Torr and a temperature range of 100-1500 K. For Ca(+) + O(2): log(10)(k(rec,0)/cm(6) molecule(-2) s(-1)) = -26.16 - 1.113log(10)T- 0.056log(10)(2)T, k(rec,infinity) = 1.4 x 10(-10) cm(3) molecule(-1) s(-1), F(c) = 0.56. For Ca(+) + CO(2): log(10)(k(rec,0)/ cm(6) molecule(-2) s(-1)) = -27.94 + 2.204log(10)T- 1.124log(10)(2)T, k(rec,infinity) = 3.5 x 10(-11) cm(3) molecule(-1) s(-1), F(c) = 0.60. For Ca(+) + H(2)O: log(10)(k(rec,0)/ cm(6) molecule(-2) s(-1)) = -23.88 - 1.823log(10)T- 0.063log(10)(2)T, k(rec,infinity) = 7.3 x 10(-11)exp(830 J mol(-1)/RT) cm(3) molecule(-1) s(-1), F(c) = 0.50 (F(c) is the broadening factor). A classical trajectory analysis of the Ca(+) + CO(2) reaction is then used to investigate the small high pressure limiting rate coefficient, which is significantly below the Langevin capture frequency. Finally, the implications of these results for calcium chemistry in the mesosphere are discussed.
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Self DE, Plane JMC, Heard DE. Kinetic study of the reactions of the sodium dimer (Na2) with a range of atmospheric species. Phys Chem Chem Phys 2006; 8:3104-15. [PMID: 16804612 DOI: 10.1039/b604305d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reactions of Na(2) with a series of atmospheric constituents were studied using a fast flow tube with detection of Na(2) by laser induced fluorescence at 656.2 nm [Na(2)(A(1)Sigma(+)(u) - X(1)Sigma(+)(g))]. The resulting rate coefficients at 298 K for the reactions of Na(2) with OH, O(2), NO(2), NO, O(3), H, H(2) and H(2)O are: (1.01(+0.35)(-0.25)) x 10(-10), (2.95 +/- 0.46) x 10(-11), (1.79(+0.51)(-0.31)) x 10(-10), (1.33 +/- 0.16) x 10(-11), (8.0(+24)(-3.0)) x 10(-11), < or =6 x 10(-12), <or =4 x 10(-15), and <or =3 x 10(-13) cm(3) molecule(-1) s(-1), respectively. The quoted uncertainties include measurement imprecision at the 1sigma level, and systematic errors. The reaction between Na(2) and OH produces chemiluminescence at 589 nm [Na(3(2)P(J) - 3(2)S(1/2))], with a measured branching ratio of (7.6(+15.0)(-3.7)) x 10(-3). The reaction enthalpies are calculated using quantum theory at the Complete Basis Set (CBS-Q) level; all reactions except Na(2) + H(2)O and Na(2) + H(2) are exothermic. The surprisingly slow reaction of Na(2) with OH is explained using trajectory calculations and consideration of the splitting between the covalent and ionic surfaces involved in the reaction, coupled with the Landau-Zener formalism. The small upper limit to the rate coefficient for the strongly exothermic reaction Na(2) + H appears to be a striking example of the light atom anomaly where the reaction is kinematically constrained.
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Affiliation(s)
- Daniel E Self
- School of Environmental Sciences, University of East Anglia, Norwich, Norfolk, NR4 7TJ, UK
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Lee EPF, Wright TG. Structures and Vibrational Frequencies of NaO3 and NaO3+: The Ionization Energy of NaO3. J Phys Chem A 2004. [DOI: 10.1021/jp0490655] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Edmond P. F. Lee
- School of Chemistry, University of Southampton, Highfield, Southampton, UK, SO17 1BJ, Department of Applied Biology and Chemical Technology, Hong Kong Polytechnic University, Hung Hom, Hong Kong, and Department of Chemistry, University of Sussex, Falmer, Brighton, UK, BN1 9QJ
| | - Timothy G. Wright
- School of Chemistry, University of Southampton, Highfield, Southampton, UK, SO17 1BJ, Department of Applied Biology and Chemical Technology, Hong Kong Polytechnic University, Hung Hom, Hong Kong, and Department of Chemistry, University of Sussex, Falmer, Brighton, UK, BN1 9QJ
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Affiliation(s)
- John M C Plane
- School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ, United Kingdom
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Self DE, M. C. Plane J. Absolute photolysis cross-sections for NaHCO3 , NaOH, NaO, NaO2and NaO3 : implications for sodium chemistry in the upper mesosphere. Phys Chem Chem Phys 2002. [DOI: 10.1039/b107078a] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Bruna PJ, Grein F. The electron-spin magnetic moments (g factors) of O3−, O3Li, and O3Na: An ab initio study. J Chem Phys 1998. [DOI: 10.1063/1.477606] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Helmer M, Plane JMC, Qian J, Gardner CS. A model of meteoric iron in the upper atmosphere. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/97jd03075] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Plane JMC, Cox RM, Qian J, Pfenninger WM, Papen GC, Gardner CS, Espy PJ. Mesospheric Na layer at extreme high latitudes in summer. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/96jd03709] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Takahashi H, Melo SML, Clemesha BR, Simonich DM, Stegman J, Witt G. Atomic hydrogen and ozone concentrations derived from simultaneous lidar and rocket airglow measurements in the equatorial region. ACTA ACUST UNITED AC 1996. [DOI: 10.1029/95jd03035] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Plane JMC, Rollason RJ. A kinetic study of the reactions of Fe(a5D) and Fe+(a6D) with N2O over the temperature range 294–850 K. ACTA ACUST UNITED AC 1996. [DOI: 10.1039/ft9969204371] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Alcamí M, Cooper IL, Mó O, Yáñez M. Potential energy surfaces of C2v and D3h ozone complexes with Li+. J Chem Phys 1995. [DOI: 10.1063/1.469638] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Clemesha BR, Simonich DM, Takahashi H, Melo SML, Plane JMC. Experimental evidence for photochemical control of the atmospheric sodium layer. ACTA ACUST UNITED AC 1995. [DOI: 10.1029/95jd01708] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Helmer M, Plane JMC. A study of the reaction NaO2+ O → NaO+ O2: Implications for the chemistry of sodium in the upper atmosphere. ACTA ACUST UNITED AC 1993. [DOI: 10.1029/93jd02033] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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