1
|
Jensen CV, Kjaergaard HG. Gas-Phase Room-Temperature Detection of the tert-Butyl Hydroperoxide Dimer. J Phys Chem A 2023; 127:6476-6485. [PMID: 37527456 DOI: 10.1021/acs.jpca.3c03702] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/03/2023]
Abstract
We have detected the tert-butyl hydroperoxide dimer, (t-BuOOH)2, in the gas phase at room temperature using conventional FTIR techniques. The dimer is identified by an asymmetric absorbance band assigned to the fundamental hydrogen-bound OHb-stretch. The weighted band maximum of the dimer OHb-stretch is located at ∼3452 cm-1, red-shifted by ∼145 cm-1 from the monomer OH-stretching band. The gas-phase dimer assignment is supported by Ar matrix isolation FTIR experiments at 12 K and experiments with a partially deuterated sample. Computationally, we find the lowest energy structure of (t-BuOOH)2 to be a doubly hydrogen bound six-membered ring with non-optimal hydrogen bond angles. We estimate the gas-phase constant of dimer formation, K, to be 0.4 (standard pressure of 1 bar) using the experimental integrated absorbance and a theoretically determined oscillator strength of the OHb-stretching band.
Collapse
Affiliation(s)
| | - Henrik G Kjaergaard
- Department of Chemistry, University of Copenhagen, 2100 Copenhagen-Ø, Denmark
| |
Collapse
|
2
|
Hansen AS, Bhagde T, Qian Y, Cavazos A, Huchmala RM, Boyer MA, Gavin-Hanner CF, Klippenstein SJ, McCoy AB, Lester MI. Infrared spectroscopic signature of a hydroperoxyalkyl radical (•QOOH). J Chem Phys 2022; 156:014301. [PMID: 34998315 DOI: 10.1063/5.0076505] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Infrared (IR) action spectroscopy is utilized to characterize a prototypical carbon-centered hydroperoxyalkyl radical (•QOOH) transiently formed in the oxidation of volatile organic compounds. The •QOOH radical formed in isobutane oxidation, 2-hydroperoxy-2-methylprop-1-yl, •CH2(CH3)2COOH, is generated in the laboratory by H-atom abstraction from tert-butyl hydroperoxide (TBHP). IR spectral features of jet-cooled and stabilized •QOOH radicals are observed from 2950 to 7050 cm-1 at energies that lie below and above the transition state barrier leading to OH radical and cyclic ether products. The observed •QOOH features include overtone OH and CH stretch transitions, combination bands involving OH or CH stretch and a lower frequency mode, and fundamental OH and CH stretch transitions. Most features arise from a single vibrational transition with band contours well simulated at a rotational temperature of 10 K. In each case, the OH products resulting from unimolecular decay of vibrationally activated •QOOH are detected by UV laser-induced fluorescence. Assignments of observed •QOOH IR transitions are guided by anharmonic frequencies computed using second order vibrational perturbation theory, a 2 + 1 model that focuses on the coupling of the OH stretch with two low-frequency torsions, as well as recently predicted statistical •QOOH unimolecular decay rates that include heavy-atom tunneling. Most of the observed vibrational transitions of •QOOH are readily distinguished from those of the TBHP precursor. The distinctive IR transitions of •QOOH, including the strong fundamental OH stretch, provide a general means for detection of •QOOH under controlled laboratory and real-world conditions.
Collapse
Affiliation(s)
- Anne S Hansen
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA
| | - Trisha Bhagde
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA
| | - Yujie Qian
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA
| | - Alyssa Cavazos
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA
| | - Rachel M Huchmala
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, USA
| | - Mark A Boyer
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, USA
| | - Coire F Gavin-Hanner
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, USA
| | - Stephen J Klippenstein
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Anne B McCoy
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, USA
| | - Marsha I Lester
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA
| |
Collapse
|
3
|
BHAGDE TRISHA, Hansen AS, Chen SG, Walsh P, Klippenstein SJ, Lester MI. Energy-resolved and time-dependent unimolecular dissociation of hydroperoxyalkyl radicals (•QOOH). Faraday Discuss 2022; 238:575-588. [DOI: 10.1039/d2fd00008c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Hydroperoxyalkyl radicals (•QOOH) are transient intermediates in the atmospheric oxidation of volatile organic compounds and combustion of hydrocarbon fuels in low temperature (< 1000 K) environments. The carbon-centered •QOOH radicals...
Collapse
|
4
|
Speak TH, Medeiros DJ, Blitz MA, Seakins PW. OH Kinetics with a Range of Nitrogen-Containing Compounds: N-Methylformamide, t-Butylamine, and N-Methyl-propane Diamine. J Phys Chem A 2021; 125:10439-10450. [PMID: 34818012 DOI: 10.1021/acs.jpca.1c08104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Emissions of amines and amides to the atmosphere are significant from both anthropogenic and natural sources, and amides can be formed as secondary pollutants. Relatively little kinetic data exist on overall rate coefficients with OH, the most important tropospheric oxidant, and even less on site-specific data which control the product distribution. Structure-activity relationships (SARs) can be used to estimate both quantities. Rate coefficients for the reaction of OH with t-butylamine (k1), N-methyl-1,3-propanediamine (k2), and N-methylformamide (k3) have been measured using laser flash photolysis coupled with laser-induced fluorescence. Proton-transfer-reaction mass spectrometry (PTR-MS) has been used to ensure the reliable introduction of these low-vapor pressure N-containing compounds and to give qualitative information on products. Supporting ab initio calculations are presented for the t-butylamine system. The following rate coefficients have been determined: k1,298K= (1.66 ± 0.20) × 10-11 cm3 molecule-1 s-1, k(T)1 = 1.65 × 10-11 (T/300)-0.69 cm3 molecule-1 s-1, k2,293K = (7.09 ± 0.22) × 10-11 cm3 molecule-1 s-1, and k3,298K = (1.03 ± 0.23) × 10-11 cm3 molecule-1 s-1. For OH + t-butylamine, ab initio calculations predict that the fraction of N-H abstraction is 0.87. The dominance of this channel was qualitatively confirmed using end-product analysis. The reaction of OH with N-methyl-1,3-propanediamine also had a negative temperature dependence, but the reduction in the rate coefficient was complicated by reagent loss. The measured rate coefficient for reaction 3 is in good agreement with a recent relative rate study. The results of this work and the literature data are compared with the recent SAR estimates for the reaction of OH with reduced nitrogen compounds. Although the SARs reproduce the overall rate coefficients for reactions, site-specific agreement with this work and other literature studies is less strong.
Collapse
Affiliation(s)
- Thomas H Speak
- School of Chemistry, University of Leeds, Leeds LS2 9JT, U.K
| | | | - Mark A Blitz
- School of Chemistry, University of Leeds, Leeds LS2 9JT, U.K.,National Centre for Atmospheric Science (NCAS), University of Leeds, Leeds LS2 9JT, U.K
| | - Paul W Seakins
- School of Chemistry, University of Leeds, Leeds LS2 9JT, U.K
| |
Collapse
|
5
|
Shchepanovska D, Shannon RJ, Curchod BFE, Glowacki DR. Nonadiabatic Kinetics in the Intermediate Coupling Regime: Comparing Molecular Dynamics to an Energy-Grained Master Equation. J Phys Chem A 2021; 125:3473-3488. [PMID: 33880919 DOI: 10.1021/acs.jpca.1c01260] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We propose and test an extension of the energy-grained master equation (EGME) for treating nonadiabatic (NA) hopping between different potential energy surfaces, which enables us to model the competition between stepwise collisional relaxation and kinetic processes which transfer population between different electronic states of the same spin symmetry. By incorporating Zhu-Nakamura theory into the EGME, we are able to treat NA passages beyond the simple Landau-Zener approximation, along with the corresponding treatments of zero-point energy and tunneling probability. To evaluate the performance of this NA-EGME approach, we carried out detailed studies of the UV photodynamics of the volatile organic compound C6-hydroperoxy aldehyde (C6-HPALD) using on-the-fly ab initio molecular dynamics and trajectory surface hopping. For this multichromophore molecule, we show that the EGME is able to capture important aspects of the dynamics, including kinetic timescales, and diabatic trapping. Such an approach provides a promising and efficient strategy for treating the long-time dynamics of photoexcited molecules in regimes which are difficult to capture using atomistic on-the-fly molecular dynamics.
Collapse
Affiliation(s)
| | - Robin J Shannon
- School of Chemistry, University of Bristol, Bristol BS8 1TS, U.K
| | | | - David R Glowacki
- School of Chemistry, University of Bristol, Bristol BS8 1TS, U.K.,Intangible Realities Laboratory, University of Bristol, Bristol BS8 1UB, U.K.,Department of Computer Science, University of Bristol, Bristol BS8 1UB, U.K
| |
Collapse
|
6
|
Hansen AS, Huchmala RM, Vogt E, Boyer MA, Bhagde T, Vansco MF, Jensen CV, Kjærsgaard A, Kjaergaard HG, McCoy AB, Lester MI. Coupling of torsion and OH-stretching in tert-butyl hydroperoxide. I. The cold and warm first OH-stretching overtone spectrum. J Chem Phys 2021; 154:164306. [DOI: 10.1063/5.0048020] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Anne S. Hansen
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA
| | - Rachel M. Huchmala
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, USA
| | - Emil Vogt
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark
| | - Mark A. Boyer
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, USA
| | - Trisha Bhagde
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA
| | - Michael F. Vansco
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA
| | - Casper V. Jensen
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark
| | - Alexander Kjærsgaard
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark
| | - Henrik G. Kjaergaard
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark
| | - Anne B. McCoy
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, USA
| | - Marsha I. Lester
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA
| |
Collapse
|
7
|
McGillen MR, Papadimitriou VC, Smith SC, Burkholder JB. FC(O)C(O)F, FC(O)CF 2C(O)F, and FC(O)CF 2CF 2C(O)F: Ultraviolet and Infrared Absorption Spectra and 248 nm Photolysis Products. J Phys Chem A 2020; 124:7123-7133. [PMID: 32786981 DOI: 10.1021/acs.jpca.0c04607] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Perfluorodicarbonyl (PFDC) compounds may be emitted directly into the atmosphere or formed in the atmospheric degradation of trace fluorinated gases, such as unsaturated perfluoro cyclic compounds. A potential atmospheric removal process for PFDCs is UV photolysis, which is presently not well-characterized. In this work, UV and infrared absorption spectra of FC(O)C(O)F, FC(O)CF2C(O)F, and FC(O)CF2CF2C(O)F (three of the simplest PFDCs) and their 248 nm photolysis products are reported. UV spectra were measured at 296 K between 190 and 320 nm using single wavelength and broadband diode array spectroscopic measurement techniques. Infrared absorption spectra were measured at 296 K using Fourier transform infrared spectroscopy between 500 and 4000 cm-1. The PFDCs are shown to be potent greenhouse gases with radiative efficiencies (well-mixed) of 0.142, 0.218, and 0.293 W m-2 ppb-1 for FC(O)C(O)F, FC(O)CF2C(O)F, and FC(O)CF2CF2C(O)F, respectively. Photolysis product yields (248 nm) were measured using pulsed laser photolysis combined with infrared absorption detection of radical products scavenged to stable bromides by reaction with Br2. BrC(O)F was identified as a major stable end product in all systems with a yield greater than ∼90%. The infrared spectrum of BrC(O)F is reported as part of this study. FC(O)CBrF2 and FC(O)CF2CBrF2 were also identified as products in the photolysis of FC(O)CF2C(O)F and FC(O)CF2CF2C(O)F, respectively, by comparison with theoretically calculated infrared absorption spectra. A carbonyl difluoride (CF2O) primary photolysis yield of ∼10% was measured in the photolysis of FC(O)C(O)F.
Collapse
Affiliation(s)
- Max R McGillen
- Chemical Sciences Laboratory, National Oceanic and Atmospheric Administration, 325 Broadway, Boulder, Colorado 80305, United States.,Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado 80309, United States
| | - Vassileios C Papadimitriou
- Chemical Sciences Laboratory, National Oceanic and Atmospheric Administration, 325 Broadway, Boulder, Colorado 80305, United States.,Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado 80309, United States
| | - Shona C Smith
- Chemical Sciences Laboratory, National Oceanic and Atmospheric Administration, 325 Broadway, Boulder, Colorado 80305, United States.,Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado 80309, United States
| | - James B Burkholder
- Chemical Sciences Laboratory, National Oceanic and Atmospheric Administration, 325 Broadway, Boulder, Colorado 80305, United States
| |
Collapse
|
8
|
Prlj A, Ibele LM, Marsili E, Curchod BFE. On the Theoretical Determination of Photolysis Properties for Atmospheric Volatile Organic Compounds. J Phys Chem Lett 2020; 11:5418-5425. [PMID: 32543205 PMCID: PMC7372557 DOI: 10.1021/acs.jpclett.0c01439] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Volatile organic compounds (VOCs) are ubiquitous atmospheric molecules that generate a complex network of chemical reactions in the troposphere, often triggered by the absorption of sunlight. Understanding the VOC composition of the atmosphere relies on our ability to characterize all of their possible reaction pathways. When considering reactions of (transient) VOCs with sunlight, the availability of photolysis rate constants, utilized in general atmospheric models, is often out of experimental reach due to the unstable nature of these molecules. Here, we show how recent advances in computational photochemistry allow us to calculate in silico the different ingredients of a photolysis rate constant, namely, the photoabsorption cross-section and wavelength-dependent quantum yields. The rich photochemistry of tert-butyl hydroperoxide, for which experimental data are available, is employed to test our protocol and highlight the strengths and weaknesses of different levels of electronic structure and nonadiabatic molecular dynamics to study the photochemistry of (transient) VOCs.
Collapse
|
9
|
Papanastasiou DK, Bernard F, Burkholder JB. Trimethylchlorosilane, (CH
3
)
3
SiCl: OH reaction kinetics and infrared spectrum. INT J CHEM KINET 2020. [DOI: 10.1002/kin.21344] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Dimitrios K. Papanastasiou
- Earth System Research LaboratoryChemical Sciences DivisionNational Oceanic and Atmospheric Administration Boulder Colorado
- Cooperative Institute for Research in Environmental SciencesUniversity of Colorado Boulder Colorado
| | - François Bernard
- Earth System Research LaboratoryChemical Sciences DivisionNational Oceanic and Atmospheric Administration Boulder Colorado
- Cooperative Institute for Research in Environmental SciencesUniversity of Colorado Boulder Colorado
| | - James B. Burkholder
- Earth System Research LaboratoryChemical Sciences DivisionNational Oceanic and Atmospheric Administration Boulder Colorado
| |
Collapse
|
10
|
Whelan CA, Blitz MA, Shannon R, Onel L, Lockhart JP, Seakins PW, Stone D. Temperature and Pressure Dependent Kinetics of QOOH Decomposition and Reaction with O2: Experimental and Theoretical Investigations of QOOH Radicals Derived from Cl + (CH3)3COOH. J Phys Chem A 2019; 123:10254-10262. [DOI: 10.1021/acs.jpca.9b08785] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Mark A. Blitz
- School of Chemistry, University of Leeds, Leeds LS2 9JT, U.K
| | - Robin Shannon
- School of Chemistry, University of Leeds, Leeds LS2 9JT, U.K
| | - Lavinia Onel
- School of Chemistry, University of Leeds, Leeds LS2 9JT, U.K
| | | | - Paul W. Seakins
- School of Chemistry, University of Leeds, Leeds LS2 9JT, U.K
| | - Daniel Stone
- School of Chemistry, University of Leeds, Leeds LS2 9JT, U.K
| |
Collapse
|
11
|
Baasandorj M, Papadimitriou VC, Burkholder JB. Rate Coefficients for the Gas-Phase Reaction of ( E)- and ( Z)-CF 3CF═CFCF 3 with the OH Radical and Cl-Atom. J Phys Chem A 2019; 123:5051-5060. [PMID: 31117596 DOI: 10.1021/acs.jpca.9b03095] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The rate coefficients, k, for the gas-phase reaction of the OH radical and Cl-atom with ( E)- and ( Z)-CF3CF═CFCF3 were measured using a relative rate technique over a range of temperature (240-375 K) and bath gas pressure (50-630 Torr, He). The obtained rate coefficients were found to be independent of pressure under these conditions. The obtained rate coefficients for the reaction of Cl-atom with ( E)- and ( Z)-CF3CF═CFCF3 at 296 K were k1(296 K) = (7.23 ± 0.3) × 10-12 cm3 molecule-1 s-1 and k2(296 K) = (6.70 ± 0.3) × 10-12 cm3 molecule-1 s-1, respectively, with the temperature dependence described by the Arrhenius expressions: k1( T) = (3.47 ± 0.35) × 10-12 exp[(210 ± 25)/ T] cm3 molecule-1 s-1 and k2( T) = (3.37 ± 0.35) × 10-12 exp[(199 ± 25)/ T] cm3 molecule-1 s-1. The rate coefficients for the OH radical reaction with ( E)- and ( Z)-CF3CF═CFCF3 were found to be k3(296-375 K) = (4.34 ± 0.45) × 10-13 cm3 molecule-1 s-1 and k4(296-375 K) = (3.30 ± 0.35) × 10-13 cm3 molecule-1 s-1, respectively. The quoted rate coefficient uncertainties are 2σ (95% confidence level) and include estimated systematic errors. The rate coefficients for the reaction of OH with a mixture of the two stereoisomers were determined using a pulsed laser photolysis-laser-induced fluorescence (PLP-LIF) technique for comparison with previous kinetic measurements using stereoisomer mixtures. The effective rate coefficient for the 0.7/0.3 ( E)/( Z) stereoisomer sample was found to be nearly independent of temperature over the range 222-375 K with a value of (4.47 ± 0.36) × 10-13 cm3 molecule-1 s-1. The atmospheric lifetimes for ( E)- and ( Z)-CF3CF═CFCF3 due to OH-reactive loss are estimated to be 25 and 35 days, respectively. The lifetime-corrected radiative efficiencies (W m-2 ppb-1) and 100 year time horizon global warming potentials derived in this work are 0.05 and 1.2 for ( E)-CF3CF═CFCF3 and 0.13 and 4.1 for ( Z)-CF3CF═CFCF3. The photochemical ozone creation potentials for ( E)- and ( Z)-CF3CF═CFCF3 are estimated to be 2.5 and 2.1, respectively.
Collapse
Affiliation(s)
- Munkhbayar Baasandorj
- Earth System Research Laboratory, Chemical Sciences Division , National Oceanic and Atmospheric Administration , 325 Broadway , Boulder , Colorado 80305-3328 , United States.,Cooperative Institute for Research in Environmental Sciences , University of Colorado , Boulder , Colorado 80309 , United States
| | - Vassileios C Papadimitriou
- Earth System Research Laboratory, Chemical Sciences Division , National Oceanic and Atmospheric Administration , 325 Broadway , Boulder , Colorado 80305-3328 , United States.,Cooperative Institute for Research in Environmental Sciences , University of Colorado , Boulder , Colorado 80309 , United States
| | - James B Burkholder
- Earth System Research Laboratory, Chemical Sciences Division , National Oceanic and Atmospheric Administration , 325 Broadway , Boulder , Colorado 80305-3328 , United States
| |
Collapse
|
12
|
Baasandorj M, Marshall P, Waterland RL, Ravishankara AR, Burkholder JB. Rate Coefficient Measurements and Theoretical Analysis of the OH + ( E)-CF 3CH═CHCF 3 Reaction. J Phys Chem A 2018; 122:4635-4646. [PMID: 29694043 DOI: 10.1021/acs.jpca.8b02771] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Rate coefficients, k, for the gas-phase reaction of the OH radical with ( E)-CF3CH═CHCF3 (( E)-1,1,1,4,4,4-hexafluoro-2-butene, HFO-1336mzz(E)) were measured over a range of temperatures (211-374 K) and bath gas pressures (20-300 Torr; He, N2) using a pulsed laser photolysis-laser-induced fluorescence (PLP-LIF) technique. k1( T) was independent of pressure over this range of conditions with k1(296 K) = (1.31 ± 0.15) × 10-13 cm3 molecule-1 s-1 and k1( T) = (6.94 ± 0.80) × 10-13exp[-(496 ± 10)/ T] cm3 molecule-1 s-1, where the uncertainties are 2σ, and the pre-exponential term includes estimated systematic error. Rate coefficients for the OD reaction were also determined over a range of temperatures (262-374 K) at 100 Torr (He). The OD rate coefficients were ∼15% greater than the OH values and showed similar temperature dependent behavior with k2( T) = (7.52 ± 0.44) × 10-13exp[-(476 ± 20)/ T] and k2(296 K) = (1.53 ± 0.15) × 10-13 cm3 molecule-1 s-1. The rate coefficients for reaction 1 were also measured using a relative rate technique between 296 and 375 K with k1(296 K) measured to be (1.22 ± 0.1) × 10-13 cm3 molecule-1 s-1, in agreement with the PLP-LIF results. In addition, the 296 K rate coefficient for the O3 + ( E)-CF3CH═CHCF3 reaction was determined to be <5.2 × 10-22 cm3 molecule-1 s-1. A theoretical computational analysis is presented to interpret the observed positive temperature dependence for the addition reaction and the significant decrease in OH reactivity compared to the ( Z)-CF3CH═CHCF3 stereoisomer reaction. The estimated atmospheric lifetime of ( E)-CF3CH═CHCF3, due to loss by reaction with OH, is estimated to be ∼90 days, while the actual lifetime will depend on the location and season of its emission. Infrared absorption spectra of ( E)-CF3CH═CHCF3 were measured and used to estimate the 100 year time horizon global warming potentials (GWP) of 32 (atmospherically well-mixed) and 14 (lifetime-adjusted).
Collapse
Affiliation(s)
- Munkhbayar Baasandorj
- Earth System Research Laboratory, Chemical Sciences Division , National Oceanic and Atmospheric Administration , 325 Broadway , Boulder , Colorado 80305-3328 , United States.,Cooperative Institute for Research in Environmental Sciences , University of Colorado , Boulder , Colorado 80309 , United States
| | - Paul Marshall
- Department of Chemistry , University of North Texas , P.O. Box 305070, Denton , Texas 76203-5070 , United States
| | | | - A R Ravishankara
- Earth System Research Laboratory, Chemical Sciences Division , National Oceanic and Atmospheric Administration , 325 Broadway , Boulder , Colorado 80305-3328 , United States
| | - James B Burkholder
- Earth System Research Laboratory, Chemical Sciences Division , National Oceanic and Atmospheric Administration , 325 Broadway , Boulder , Colorado 80305-3328 , United States
| |
Collapse
|
13
|
Blitz MA, Salter RJ, Heard DE, Seakins PW. An Experimental and Master Equation Study of the Kinetics of OH/OD + SO 2: The Limiting High-Pressure Rate Coefficients. J Phys Chem A 2017; 121:3184-3191. [PMID: 28365987 DOI: 10.1021/acs.jpca.7b01295] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The kinetics of the reaction OH/OD + SO2 were studied using a laser flash photolysis/laser-induced fluorescence technique. Evidence for two-photon photolysis of SO2 at 248 nm is presented and quantified, and which appears to have been evident to some extent in most previous photolysis studies, potentially leading to values for the rate coefficient k1 that are too large. The kinetics of the reaction OH(v = 0) + SO2 (T = 295 K, p = 25-300 torr) were measured under conditions where SO2 photolysis was taken into account. These results, together with literature data, were modeled using a master equation analysis. This analysis highlighted problems with the literature data: the rate coefficients derived from flash photolysis data were generally too high and from the flow tube data too low. Our best estimate of the high-pressure limiting rate coefficient k1∞ was obtained from selected data and gives a value of (7.8 ± 2.2) × 10-13 cm3 molecule-1 s-1, which is lower than that recommended in the literature. A parametrized form of k1([N2],T) is provided. The OD(v = 0) + SO2 (T = 295 K, p = 25-300 torr) data are reported for the first time, and master equation analysis reinforces our assignment of k1∞.
Collapse
Affiliation(s)
| | - Robert J Salter
- Deloitte MCS , 3 Rivergate, Temple Quay, Bristol BR1 6GD, U.K
| | | | | |
Collapse
|
14
|
Howes NUM, Lockhart JPA, Blitz MA, Carr SA, Baeza-Romero MT, Heard DE, Shannon RJ, Seakins PW, Varga T. Observation of a new channel, the production of CH 3, in the abstraction reaction of OH radicals with acetaldehyde. Phys Chem Chem Phys 2016; 18:26423-26433. [PMID: 27711478 DOI: 10.1039/c6cp03970g] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Using laser flash photolysis coupled to photo-ionization time-of-flight mass spectrometry (PIMS), methyl radicals (CH3) have been detected as primary products from the reaction of OH radicals with acetaldehyde (ethanal, CH3CHO) with a yield of ∼15% at 1-2 Torr of helium bath gas. Supporting measurements based on laser induced fluorescence studies of OH recycling in the OH/CH3CHO/O2 system are consistent with the PIMS study. Master equation calculations suggest that the origin of the methyl radicals is from prompt dissociation of chemically activated acetyl products and hence is consistent with previous studies which have shown that abstraction, rather than addition/elimination, is the sole route for the OH + acetaldehyde reaction. However, the observation of a significant methyl product yield suggests that energy partitioning in the reaction is different from the typical early barrier mechanism where reaction exothermicity is channeled preferentially into the newly formed bond. The master equation calculations predict atmospheric yields of methyl radicals of ∼9%. The implications of the observations in atmospheric and combustion chemistry are briefly discussed.
Collapse
Affiliation(s)
- Neil U M Howes
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, UK.
| | | | - Mark A Blitz
- National Centre for Atmospheric Science, University of Leeds, Leeds, LS2 9JT, UK
| | - Scott A Carr
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, UK.
| | | | - Dwayne E Heard
- National Centre for Atmospheric Science, University of Leeds, Leeds, LS2 9JT, UK
| | - Robin J Shannon
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, UK.
| | - Paul W Seakins
- National Centre for Atmospheric Science, University of Leeds, Leeds, LS2 9JT, UK
| | - T Varga
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, UK.
| |
Collapse
|
15
|
Baasandorj M, Burkholder JB. Rate Coefficient for the Gas-Phase OH + CHF=CF2Reaction between 212 and 375 K. INT J CHEM KINET 2016. [DOI: 10.1002/kin.21027] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Munkhbayar Baasandorj
- Earth System Research Laboratory; Chemical Sciences Division; National Oceanic and Atmospheric Administration; Boulder CO 80305
- Cooperative Institute for Research in Environmental Sciences; University of Colorado; Boulder CO 80309
| | - James B. Burkholder
- Earth System Research Laboratory; Chemical Sciences Division; National Oceanic and Atmospheric Administration; Boulder CO 80305
| |
Collapse
|
16
|
Papadimitriou VC, Burkholder JB. OH Radical Reaction Rate Coefficients, Infrared Spectrum, and Global Warming Potential of (CF3)2CFCH═CHF (HFO-1438ezy(E)). J Phys Chem A 2016; 120:6618-28. [DOI: 10.1021/acs.jpca.6b06096] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Vassileios C. Papadimitriou
- Earth
System Research Laboratory, Chemical Sciences Division, National Oceanic and Atmospheric Administration, 325 Broadway, Boulder, Colorado 80305, United States
- Cooperative
Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado 80309, United States
- Laboratory
of Photochemistry and Chemical Kinetics, Department of Chemistry, University of Crete, Vassilika Vouton, 71003 Heraklion, Crete, Greece
| | - James B. Burkholder
- Earth
System Research Laboratory, Chemical Sciences Division, National Oceanic and Atmospheric Administration, 325 Broadway, Boulder, Colorado 80305, United States
| |
Collapse
|
17
|
Foreman ES, Kapnas KM, Murray C. Reactions between Criegee Intermediates and the Inorganic Acids HCl and HNO3: Kinetics and Atmospheric Implications. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201604662] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
| | - Kara M. Kapnas
- Department of Chemistry; University of California, Irvine; Irvine CA 92697 USA
| | - Craig Murray
- Department of Chemistry; University of California, Irvine; Irvine CA 92697 USA
| |
Collapse
|
18
|
Foreman ES, Kapnas KM, Murray C. Reactions between Criegee Intermediates and the Inorganic Acids HCl and HNO3: Kinetics and Atmospheric Implications. Angew Chem Int Ed Engl 2016; 55:10419-22. [DOI: 10.1002/anie.201604662] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Revised: 07/01/2016] [Indexed: 11/06/2022]
Affiliation(s)
| | - Kara M. Kapnas
- Department of Chemistry; University of California, Irvine; Irvine CA 92697 USA
| | - Craig Murray
- Department of Chemistry; University of California, Irvine; Irvine CA 92697 USA
| |
Collapse
|
19
|
Bunkan AJC, Hetzler J, Mikoviny T, Wisthaler A, Nielsen CJ, Olzmann M. The reactions of N-methylformamide and N,N-dimethylformamide with OH and their photo-oxidation under atmospheric conditions: experimental and theoretical studies. Phys Chem Chem Phys 2015; 17:7046-59. [DOI: 10.1039/c4cp05805d] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The atmospheric oxidation of amides is studied with a combination of laser photolysis and smog chamber experiments along with quantum chemical and statistical rate theory calculations.
Collapse
Affiliation(s)
- Arne Joakim C. Bunkan
- Center for Theoretical and Computational Chemistry
- Department of Chemistry
- University of Oslo
- 0315 Oslo
- Norway
| | - Jens Hetzler
- Institut für Physikalische Chemie
- Karlsruher Institut für Technologie (KIT)
- 76131 Karlsruhe
- Germany
| | - Tomáš Mikoviny
- Institute for Ion Physics and Applied Physics
- University of Innsbruck
- A-6020 Innsbruck
- Austria
| | - Armin Wisthaler
- Institute for Ion Physics and Applied Physics
- University of Innsbruck
- A-6020 Innsbruck
- Austria
| | - Claus J. Nielsen
- Center for Theoretical and Computational Chemistry
- Department of Chemistry
- University of Oslo
- 0315 Oslo
- Norway
| | - Matthias Olzmann
- Institut für Physikalische Chemie
- Karlsruher Institut für Technologie (KIT)
- 76131 Karlsruhe
- Germany
| |
Collapse
|
20
|
Gierczak T, Baasandorj M, Burkholder JB. OH + (E)- and (Z)-1-Chloro-3,3,3-trifluoropropene-1 (CF3CH═CHCl) Reaction Rate Coefficients: Stereoisomer-Dependent Reactivity. J Phys Chem A 2014; 118:11015-25. [DOI: 10.1021/jp509127h] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Tomasz Gierczak
- Earth System Research
Laboratory, Chemical Sciences Division, National Oceanic and Atmospheric
Administration, 325 Broadway, Boulder Colorado 80305, United States
- Cooperative
Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado 80309, United States
| | - M. Baasandorj
- Earth System Research
Laboratory, Chemical Sciences Division, National Oceanic and Atmospheric
Administration, 325 Broadway, Boulder Colorado 80305, United States
- Cooperative
Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado 80309, United States
| | - James B. Burkholder
- Earth System Research
Laboratory, Chemical Sciences Division, National Oceanic and Atmospheric
Administration, 325 Broadway, Boulder Colorado 80305, United States
| |
Collapse
|
21
|
Onel L, Blitz M, Dryden M, Thonger L, Seakins P. Branching ratios in reactions of OH radicals with methylamine, dimethylamine, and ethylamine. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:9935-9942. [PMID: 25072999 DOI: 10.1021/es502398r] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The branching ratios for the reaction of the OH radical with the primary and secondary alkylamines: methylamine (MA), dimethylamine (DMA), and ethylamine (EA), have been determined using the technique of pulsed laser photolysis-laser-induced fluorescence. Titration of the carbon-centered radical, formed following the initial OH abstraction, with oxygen to give HO2 and an imine, followed by conversion of HO2 to OH by reaction with NO, resulted in biexponential OH decay traces on a millisecond time scale. Analysis of the biexponential curves gave the HO2 yield, which equaled the branching ratio for abstraction at αC-H position, r(αC-H). The technique was validated by reproducing known branching ratios for OH abstraction for methanol and ethanol. For the amines studied in this work (all at 298 K): r(αC-H,MA) = 0.76 ± 0.08, r(αC-H,DMA) = 0.59 ± 0.07, and r(αC-H,EA) = 0.49 ± 0.06 where the errors are a combination in quadrature of statistical errors at the 2σ level and an estimated 10% systematic error. The branching ratios r(αC-H) for OH reacting with (CH3)2NH and CH3CH2NH2 are in agreement with those obtained for the OD reaction with (CH3)2ND (d-DMA) and CH3CH2ND2 (d-EA): r(αC-H,d-DMA) = 0.71 ± 0.12 and r(αC-H,d-EA) = 0.54 ± 0.07. A master equation analysis (using the MESMER package) based on potential energy surfaces from G4 theory was used to demonstrate that the experimental determinations are unaffected by formation of stabilized peroxy radicals and to estimate atmospheric pressure yields. The branching ratio for imine formation through the reaction of O2 with α carbon-centered radicals at 1 atm of N2 are estimated as r(CH2NH2) = 0.79 ± 0.15, r(CH2NHCH3) = 0.72 ± 0.19, and r(CH3CHNH2) = 0.50 ± 0.18. The implications of this work on the potential formation of nitrosamines and nitramines are briefly discussed.
Collapse
Affiliation(s)
- Lavinia Onel
- School of Chemistry, University of Leeds , Leeds, LS2 9JT, U.K
| | | | | | | | | |
Collapse
|
22
|
Xu L, Kollman MS, Song C, Shilling JE, Ng NL. Effects of NOx on the volatility of secondary organic aerosol from isoprene photooxidation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:2253-62. [PMID: 24471688 DOI: 10.1021/es404842g] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The effects of NOx on the volatility of the secondary organic aerosol (SOA) formed from isoprene photooxidation are investigated in environmental chamber experiments. Two types of experiments are performed. In HO2-dominant experiments, organic peroxy radicals (RO2) primarily react with HO2. In mixed experiments, RO2 reacts through multiple pathways, including with NO, NO2, and HO2. The volatility and oxidation state of isoprene SOA are sensitive to and exhibit a nonlinear dependence on NOx levels. Depending on the NOx levels, the SOA formed in mixed experiments can be of similar or lower volatility compared to that formed in HO2-dominant experiments. The dependence of SOA yield, volatility, and oxidation state on the NOx level likely arises from gas-phase RO2 chemistry and succeeding particle-phase oligomerization reactions. The NOx level also plays a strong role in SOA aging. While the volatility of SOA in mixed experiments does not change substantially over time, SOA becomes less volatile and more oxidized as oxidation progresses in HO2-dominant experiments.
Collapse
Affiliation(s)
- Lu Xu
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology , Atlanta, Georgia 30332, United States
| | | | | | | | | |
Collapse
|
23
|
Hsieh S, Vushe R, Tun YT, Vallejo JL. Trends in organic hydroperoxide photodissociation and absorption cross sections between 266 and 377 nm. Chem Phys Lett 2014. [DOI: 10.1016/j.cplett.2013.11.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
24
|
Onel L, Thonger L, Blitz MA, Seakins PW, Bunkan AJC, Solimannejad M, Nielsen CJ. Gas-Phase Reactions of OH with Methyl Amines in the Presence or Absence of Molecular Oxygen. An Experimental and Theoretical Study. J Phys Chem A 2013; 117:10736-45. [DOI: 10.1021/jp406522z] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- L. Onel
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - L. Thonger
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - M. A. Blitz
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - P. W. Seakins
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - A. J. C. Bunkan
- CTCC,
Department of Chemistry, University of Oslo, P.O.Box 1033 Blindern, 0315 Oslo, Norway
| | - M. Solimannejad
- CTCC,
Department of Chemistry, University of Oslo, P.O.Box 1033 Blindern, 0315 Oslo, Norway
| | - C. J. Nielsen
- CTCC,
Department of Chemistry, University of Oslo, P.O.Box 1033 Blindern, 0315 Oslo, Norway
| |
Collapse
|
25
|
Lockhart J, Blitz MA, Heard DE, Seakins PW, Shannon RJ. Mechanism of the Reaction of OH with Alkynes in the Presence of Oxygen. J Phys Chem A 2013; 117:5407-18. [DOI: 10.1021/jp404233b] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- James Lockhart
- School
of Chemistry, University of Leeds, Leeds,
LS2 9JT, U.K
| | - Mark A. Blitz
- School
of Chemistry, University of Leeds, Leeds,
LS2 9JT, U.K
| | - Dwayne E. Heard
- School
of Chemistry, University of Leeds, Leeds,
LS2 9JT, U.K
| | - Paul W. Seakins
- School
of Chemistry, University of Leeds, Leeds,
LS2 9JT, U.K
| | | |
Collapse
|
26
|
McGillen MR, Baasandorj M, Burkholder JB. Gas-phase rate coefficients for the OH + n-, i-, s-, and t-butanol reactions measured between 220 and 380 K: non-Arrhenius behavior and site-specific reactivity. J Phys Chem A 2013; 117:4636-56. [PMID: 23627621 DOI: 10.1021/jp402702u] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Butanol (C4H9OH) is a potential biofuel alternative in fossil fuel gasoline and diesel formulations. The usage of butanol would necessarily lead to direct emissions into the atmosphere; thus, an understanding of its atmospheric processing and environmental impact is desired. Reaction with the OH radical is expected to be the predominant atmospheric removal process for the four aliphatic isomers of butanol. In this work, rate coefficients, k, for the gas-phase reaction of the n-, i-, s-, and t-butanol isomers with the OH radical were measured under pseudo-first-order conditions in OH using pulsed laser photolysis to produce OH radicals and laser induced fluorescence to monitor its temporal profile. Rate coefficients were measured over the temperature range 221-381 K at total pressures between 50 and 200 Torr (He). The reactions exhibited non-Arrhenius behavior over this temperature range and no dependence on total pressure with k(296 K) values of (9.68 ± 0.75), (9.72 ± 0.72), (8.88 ± 0.69), and (1.04 ± 0.08) (in units of 10(-12) cm(3) molecule(-1) s(-1)) for n-, i-, s-, and t-butanol, respectively. The quoted uncertainties are at the 2σ level and include estimated systematic errors. The observed non-Arrhenius behavior is interpreted here to result from a competition between the available H-atom abstraction reactive sites, which have different activation energies and pre-exponential factors. The present results are compared with results from previous kinetic studies, structure-activity relationships (SARs), and theoretical calculations and the discrepancies are discussed. Results from this work were combined with available high temperature (1200-1800 K) rate coefficient data and room temperature reaction end-product yields, where available, to derive a self-consistent site-specific set of reaction rate coefficients of the form AT(n) exp(-E/RT) for use in atmospheric and combustion chemistry modeling.
Collapse
Affiliation(s)
- Max R McGillen
- Chemical Sciences Division, Earth System Research Laboratory, National Oceanic and Atmospheric Administration, 325 Broadway, Boulder, Colorado 80305, USA
| | | | | |
Collapse
|
27
|
Zádor J, Huang H, Welz O, Zetterberg J, Osborn DL, Taatjes CA. Directly measuring reaction kinetics of ˙QOOH – a crucial but elusive intermediate in hydrocarbon autoignition. Phys Chem Chem Phys 2013; 15:10753-60. [DOI: 10.1039/c3cp51185e] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
28
|
Ren H, Zhang L, Wang R, Pan X. Theoretical Studies on the Mechanisms and Dynamics of OH Radical with (CH3)3COOH and (CH3)2CHOOH. J Phys Chem A 2012; 116:10647-55. [DOI: 10.1021/jp3064905] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- He Ren
- Faculty of Chemistry, Institute of
Functional Material
Chemistry, Northeast Normal University,
130024 Changchun, People’s Republic of China
| | - Lingling Zhang
- Faculty of Chemistry, Institute of
Functional Material
Chemistry, Northeast Normal University,
130024 Changchun, People’s Republic of China
| | - Rongshun Wang
- Faculty of Chemistry, Institute of
Functional Material
Chemistry, Northeast Normal University,
130024 Changchun, People’s Republic of China
| | - Xiumei Pan
- Faculty of Chemistry, Institute of
Functional Material
Chemistry, Northeast Normal University,
130024 Changchun, People’s Republic of China
| |
Collapse
|
29
|
Shemesh D, Gerber RB. Femtosecond timescale deactivation of electronically excited peroxides at ice surfaces. Mol Phys 2012. [DOI: 10.1080/00268976.2012.666279] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
30
|
Yee LD, Craven JS, Loza CL, Schilling KA, Ng NL, Canagaratna MR, Ziemann PJ, Flagan RC, Seinfeld JH. Secondary organic aerosol formation from low-NO(x) photooxidation of dodecane: evolution of multigeneration gas-phase chemistry and aerosol composition. J Phys Chem A 2012; 116:6211-30. [PMID: 22424261 DOI: 10.1021/jp211531h] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The extended photooxidation of and secondary organic aerosol (SOA) formation from dodecane (C(12)H(26)) under low-NO(x) conditions, such that RO(2) + HO(2) chemistry dominates the fate of the peroxy radicals, is studied in the Caltech Environmental Chamber based on simultaneous gas and particle-phase measurements. A mechanism simulation indicates that greater than 67% of the initial carbon ends up as fourth and higher generation products after 10 h of reaction, and simulated trends for seven species are supported by gas-phase measurements. A characteristic set of hydroperoxide gas-phase products are formed under these low-NO(x) conditions. Production of semivolatile hydroperoxide species within three generations of chemistry is consistent with observed initial aerosol growth. Continued gas-phase oxidation of these semivolatile species produces multifunctional low volatility compounds. This study elucidates the complex evolution of the gas-phase photooxidation chemistry and subsequent SOA formation through a novel approach comparing molecular level information from a chemical ionization mass spectrometer (CIMS) and high m/z ion fragments from an Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS). Combination of these techniques reveals that particle-phase chemistry leading to peroxyhemiacetal formation is the likely mechanism by which these species are incorporated in the particle phase. The current findings are relevant toward understanding atmospheric SOA formation and aging from the "unresolved complex mixture," comprising, in part, long-chain alkanes.
Collapse
Affiliation(s)
- Lindsay D Yee
- Division of Engineering and Applied Science, California Institute of Technology, Pasadena, California 91125, United States
| | | | | | | | | | | | | | | | | |
Collapse
|
31
|
Hsieh S, Thida T, Nyamumbo MK, Smith KA, Naamad N, Linck RG. O–H Stretch Overtone Excitation of Ethyl Hydroperoxide Conformers. J Phys Chem A 2011; 115:14040-4. [DOI: 10.1021/jp208467f] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Shizuka Hsieh
- Chemistry Department, Smith College, Northampton, Massachusetts 01063, United States
| | - Thida Thida
- Chemistry Department, Smith College, Northampton, Massachusetts 01063, United States
| | - Margaret K. Nyamumbo
- Chemistry Department, Smith College, Northampton, Massachusetts 01063, United States
| | - Kelly A. Smith
- Chemistry Department, Smith College, Northampton, Massachusetts 01063, United States
| | - Noah Naamad
- Chemistry Department, Smith College, Northampton, Massachusetts 01063, United States
| | - Robert G. Linck
- Chemistry Department, Smith College, Northampton, Massachusetts 01063, United States
| |
Collapse
|
32
|
Baasandorj M, Ravishankara A, Burkholder JB. Atmospheric Chemistry of (Z)-CF3CH═CHCF3: OH Radical Reaction Rate Coefficient and Global Warming Potential. J Phys Chem A 2011; 115:10539-49. [DOI: 10.1021/jp206195g] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Munkhbayar Baasandorj
- Earth System Research Laboratory, Chemical Sciences Division, National Oceanic and Atmospheric Administration, 325 Broadway, Boulder, Colorado 80305-3328, United States
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado 80309, United States
| | - A.R. Ravishankara
- Earth System Research Laboratory, Chemical Sciences Division, National Oceanic and Atmospheric Administration, 325 Broadway, Boulder, Colorado 80305-3328, United States
| | - James B. Burkholder
- Earth System Research Laboratory, Chemical Sciences Division, National Oceanic and Atmospheric Administration, 325 Broadway, Boulder, Colorado 80305-3328, United States
| |
Collapse
|