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Karsili TNV, Marchetti B, Lester MI, Ashfold MNR. Electronic Absorption Spectroscopy and Photochemistry of Criegee Intermediates. Photochem Photobiol 2023; 99:4-18. [PMID: 35713380 DOI: 10.1111/php.13665] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 06/14/2022] [Indexed: 01/26/2023]
Abstract
Interest in Criegee intermediates (CIs), often termed carbonyl oxides, and their role in tropospheric chemistry has grown massively since the demonstration of laboratory-based routes to their formation and characterization in the gas phase. This article reviews current knowledge regarding the electronic spectroscopy of atmospherically relevant CIs like CH2 OO, CH3 CHOO, (CH3 )2 COO and larger CIs like methyl vinyl ketone oxide and methacrolein oxide that are formed in the ozonolysis of isoprene, and of selected conjugated carbene-derived CIs of interest in the synthetic chemistry community. Of the aforementioned atmospherically relevant CIs, all except CH2 OO and (CH3 )2 COO exist in different conformers which, under tropospheric conditions, can display strikingly different thermal loss rates via unimolecular and bimolecular processes. Calculated photolysis rates based on their absorption properties suggest that solar photolysis will rarely be a significant contributor to the total loss rate for any CI under tropospheric conditions. Nonetheless, there is ever-growing interest in the absorption cross sections and primary photochemistry of CIs following excitation to the strongly absorbing 1 ππ* state, and how this varies with CI, with conformer and with excitation wavelength. The later part of this review surveys the photochemical data reported to date, including a range of studies that demonstrate prompt photo-induced fission of the terminal O-O bond, and speculates about possible alternate decay processes that could occur following non-adiabatic coupling to, and dissociation from, highly internally excited levels of the electronic ground state of a CI.
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Affiliation(s)
| | | | - Marsha I Lester
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA
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2
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Yang J, Li Y, Makroni L, Liu F. The photoisomerization mechanism of methacrolein oxide (MACR-OO): the cyclic dioxole formation pathway revealed. Phys Chem Chem Phys 2022; 24:22531-22537. [PMID: 36111632 DOI: 10.1039/d2cp03028d] [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
Methacrolein oxide (MACR-OO), the isopropenyl substituted Criegee intermediate (CI), is one product of isoprene ozonolysis. In this work, we report MACR-OO's photo-isomerization paths with electronic structure calculation at the CASSCF and MS-CASPT2 levels and trajectory surface-hopping (TSH) nonadiabatic dynamics simulation at the CASSCF level. Our calculated results show that the ring-closure is the dominant photo-induced unimolecular isomerization of MACR-OO in the S1 state. In addition, a new photo-induced ring-closure to heterocyclopentane dioxole in syn_syn-MACR-OO is found. The findings of MACR-OO are expected to deepen the understanding of the substituted CIs and their photochemistry.
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Affiliation(s)
- Jiawei Yang
- Key Laboratory of Applied Surface and Colloid Chemistry of Ministry of Education, Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an, Shaanxi 710119, People's Republic of China.
| | - Yazhen Li
- Key Laboratory of Applied Surface and Colloid Chemistry of Ministry of Education, Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an, Shaanxi 710119, People's Republic of China.
| | - Lily Makroni
- Key Laboratory of Applied Surface and Colloid Chemistry of Ministry of Education, Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an, Shaanxi 710119, People's Republic of China.
| | - Fengyi Liu
- Key Laboratory of Applied Surface and Colloid Chemistry of Ministry of Education, Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an, Shaanxi 710119, People's Republic of China.
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3
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Zhou Z, Lakey PSJ, von Domaros M, Wise N, Tobias DJ, Shiraiwa M, Abbatt JPD. Multiphase Ozonolysis of Oleic Acid-Based Lipids: Quantitation of Major Products and Kinetic Multilayer Modeling. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:7716-7728. [PMID: 35671499 DOI: 10.1021/acs.est.2c01163] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Commonly found in atmospheric aerosols, cooking oils, and human sebum, unsaturated lipids rapidly decay upon exposure to ozone, following the Criegee mechanism. Here, the gas-surface ozonolysis of three oleic acid-based compounds was studied in a reactor and indoors. Under dry conditions, quantitative product analyses by 1H NMR indicate up to 79% molar yield of stable secondary ozonides (SOZs) in oxidized triolein and methyl oleate coatings. Elevated relative humidity (RH) significantly suppresses the SOZ yields, enhancing the formation of condensed-phase aldehydes and volatile C9 products. Along with kinetic parameters informed by molecular dynamics simulations, these results were used as constraints in a kinetic multilayer model (KM-GAP) simulating triolein ozonolysis. Covering a wide range of coating thicknesses and ozone levels, the model predicts a much faster decay near the gas-lipid interface compared to the bulk. Although the dependence of RH on SOZ yields is well predicted, the model overestimates the production of H2O2 and aldehydes. With negligible dependence on RH, the product composition for oxidized oleic acid is substantially affected by a competitive reaction between Criegee intermediates (CIs) and carboxylic acids. The resulting α-acyloxyalkyl hydroperoxides (α-AAHPs) have much higher molar yields (29-38%) than SOZs (12-16%). Overall, the ozone-lipid chemistry could affect the indoor environment through "crust" accumulation on surfaces and volatile organic compound (VOC) emission. In the atmosphere, the peroxide formation and changes in particle hygroscopicity may have effects on climate. The related health impacts are also discussed.
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Affiliation(s)
- Zilin Zhou
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5S 3H6, Canada
| | - Pascale S J Lakey
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Michael von Domaros
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Natsuko Wise
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Douglas J Tobias
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Manabu Shiraiwa
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Jonathan P D Abbatt
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5S 3H6, Canada
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4
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Dyakov YA, Adamson SO, Wang PK, Vetchinkin AS, Golubkov GV, Peskov VD, Rodionov AI, Syromyatnikov AG, Umanskii SY, Shestakov DV, Golubkov MG. Excited State Dynamics of CH3CHOO Criegee Intermediates in the Upper Atmosphere of the Earth. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY B 2022. [DOI: 10.1134/s1990793122030149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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5
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Wang L, Wu Z, Lu B, Zeng X. Spectroscopic characterization and photochemistry of the Criegee intermediate CF 3C(H)OO. J Environ Sci (China) 2022; 114:160-169. [PMID: 35459481 DOI: 10.1016/j.jes.2021.08.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 08/02/2021] [Accepted: 08/03/2021] [Indexed: 06/14/2023]
Abstract
Criegee intermediates (CIs), also known as carbonyl oxide, are reactive intermediates that play an important role in the atmospheric chemistry. Investigation on the structures and reactivity of CIs is of fundamental importance in understanding the underlying mechanism of their atmospheric reactions. In sharp contrast to the intensively studied parent molecule (CH2OO) and the alkyl-substituted derivatives, the knowledge about the fluorinated analogue CF3C(H)OO is scarce. By carefully heating the triplet carbene CF3CH in an O2-doped Ar-matrix to 35 K, the elusive carbonyl oxide CF3C(H)OO in syn- and anti-conformations has been generated and characterized with infrared (IR) and ultraviolet-visible (UV-vis) spectroscopy. The spectroscopic identification is supported by 18O-labeling experiments and quantum chemical calculations at the B3LYP/6-311++G(3df,3pd) and MP2/6-311++G(2d,2p) levels. Upon the long-wavelength irradiation (λ > 680 nm), both conformers of CF3C(H)OO decompose to give trifluoroacetaldehyde CF3C(H)O and simultaneously rearrange to the isomeric dioxirane, cyclic-CF3CH(OO), which undergoes isomerization to the lowest-energy carboxylic acid CF3C(O)OH upon UV-light excitation at 365 nm. The O2-oxidation of CF3CH via the intermediacy of CF3C(H)OO and cyclic-CF3CH(OO) might provide new insight into the mechanism for the degradation of hydro-chlorofluorocarbon CF3CHCl2 (HCFC-123) in the atmosphere.
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Affiliation(s)
- Lina Wang
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysts and Innovative Materials, Fudan University, Shanghai 200433, China.
| | - Zhuang Wu
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysts and Innovative Materials, Fudan University, Shanghai 200433, China
| | - Bo Lu
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysts and Innovative Materials, Fudan University, Shanghai 200433, China
| | - Xiaoqing Zeng
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysts and Innovative Materials, Fudan University, Shanghai 200433, China.
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Ji YT, Lee YP. Dynamics of Reaction CH 3CHI + O 2 Investigated via Infrared Emission of Products CO, CO 2, and OH. J Phys Chem A 2021; 125:8373-8385. [PMID: 34524829 DOI: 10.1021/acs.jpca.1c05610] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The reaction CH3CHI + O2 has been commonly employed in laboratories to produce a methyl-substituted Criegee intermediate CH3CHOO, but the detailed dynamics of this reaction remain unexplored. We carried out this reaction by irradiating a flowing mixture of CH3CHI2 (∼70 mTorr) and O2 (∼4 and 8 Torr) at 308 or 248 nm and observed infrared emission of the products with a step-scan Fourier-transform spectrometer. Upon irradiation at 248 nm with O2 ∼4 Torr, a Boltzmann distribution of CO (v ≤ 4, J ≤ 25) with average vibrational energy (12 ± 2) kJ mol-1 and of OH (v = 1, J ≤ 5.5) were observed and assigned to be produced from the decomposition of CH3C(O)OH* to form CO + CH3OH and OH + CH3CO, respectively. The observed broadband emission of CO2 was simulated with two vibrational distributions of average energies (42 ± 3) and (114 ± 6) kJ mol-1 and assigned to be produced from the decomposition of CH3C(O)OH* and (methyl dioxirane)*, respectively. The results upon irradiation of the sample at 308 nm are similar, likely indicating a small fraction of energy partition into these products and rapid thermalization of CH3CHI*. Compared with reaction CH2I + O2, the title reaction yielded products with much less internal excitation, consistent with the expectation that these observed products receive much less fraction of available energy upon fragmentation when an additional methyl moiety was present in the parent. The large-v component of CO observed in experiments of CH2I + O2 at 248 nm, produced from secondary reaction HCO + O2, was absent in this work because the corresponding secondary reaction CH3CO + O2 in decomposition of CH3CHOO* produces α-lactone + OH or H2CO + CO + OH.
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Affiliation(s)
- Ya-Tsang Ji
- Department of Applied Chemistry and Institute of Molecular Science, National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan
| | - Yuan-Pern Lee
- Department of Applied Chemistry and Institute of Molecular Science, National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan.,Center for Emergent Functional Matter Science, National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan.,Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106319, Taiwan
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Dyakov YA, Adamson SO, Wang PK, Vetchinkin AS, Golubkov GV, Morozov II, Umanskii SY, Chaikina YA, Golubkov MG. Collisional Dissociation of Crieege CH3CHOO and Methane Intermediates in the Earth’s Upper Atmosphere. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY B 2021. [DOI: 10.1134/s1990793121050134] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Dyakov YA, Adamson S, Wang PK, Golubkov GV, Olkhov OA, Peskov VD, Rodionov ID, Rodionova IP, Rodionov AI, Shapovalov VL, Shestakov DV, Golubkov MG. Isomerization and Decay of a Criegee Intermediate CH3CHOO in the Earth’s Upper Atmosphere. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY B 2021. [DOI: 10.1134/s1990793121030040] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Liu J, Liu Y, Yang J, Zeng XC, He X. Directional Proton Transfer in the Reaction of the Simplest Criegee Intermediate with Water Involving the Formation of Transient H 3O . J Phys Chem Lett 2021; 12:3379-3386. [PMID: 33784110 DOI: 10.1021/acs.jpclett.1c00448] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The reaction of Criegee intermediates with water vapor has been widely known as a key Criegee reaction in the troposphere. Herein, we investigated the reaction of the smallest Criegee intermediate, CH2OO, with a water cluster through fragment-based ab initio molecular dynamics simulations at the MP2/aug-cc-pVDZ level. Our results show that the CH2OO-water reaction could occur not only at the air/water interface but also inside the water cluster. Moreover, more than one reactive water molecules are required for the CH2OO-water reaction, which is always initiated from the Criegee carbon atom and ends at the terminal Criegee oxygen atom via a directional proton transfer process. The observed reaction pathways include the loop-structure-mediated and stepwise mechanisms, and the latter involves the formation of transient H3O+. The lifetime of transient H3O+ is on the order of a few picoseconds, which may impact the atmospheric budget of the other trace gases in the actual atmosphere.
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Affiliation(s)
- Jinfeng Liu
- Department of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, 200062, China
| | - Yanqing Liu
- Department of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Jinrong Yang
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, 200062, China
| | - Xiao Cheng Zeng
- Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68588, United States
| | - Xiao He
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, 200062, China
- NYU-ECNU Center for Computational Chemistry at NYU, Shanghai, Shanghai, 200062, China
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Li YZ, Yang JW, Makroni L, Wang WL, Liu FY. Photodynamics of methyl-vinyl Criegee intermediate: Different conical intersections govern the fates of syn/anti configurations. CHINESE J CHEM PHYS 2020. [DOI: 10.1063/1674-0068/cjcp2006088] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Ya-zhen Li
- Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi’an 710062, China
| | - Jia-wei Yang
- Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi’an 710062, China
| | - Lily Makroni
- Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi’an 710062, China
| | - Wen-liang Wang
- Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi’an 710062, China
| | - Feng-yi Liu
- Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi’an 710062, China
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Yang X, Deng J, Li D, Chen J, Xu Y, Zhang K, Shang X, Cao Q. Transient species in the ozonolysis of tetramethylethene. J Environ Sci (China) 2020; 95:210-216. [PMID: 32653182 DOI: 10.1016/j.jes.2020.03.027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Revised: 02/12/2020] [Accepted: 03/17/2020] [Indexed: 06/11/2023]
Abstract
The reaction of alkenes with ozone has great effect on atmospheric oxidation, its transient species can produce OH radicals and contribute to the formation of secondary organic aerosols (SOA). In the present study, the reaction of tetramethylethene (TME) with ozone was investigated using self-assembled low temperature matrix isolation system. The TME and ozone were co-deposited on a salt plate at 15 K, and then slowly warmed up the plate. The first transient species primary ozonide (POZ) was detected, indicating that the reaction followed Criegee mechanism. Then POZ began to decompose at 180 K. However, secondary ozonide (SOZ) was not observed according to Criegee mechanism. Probably, Criegee Intermediate (CI) did not react with inert carbonyl of acetone, but with remaining TME formed tetra-methyl epoxide (EPO).
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Affiliation(s)
- Xiaolu Yang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Jianguo Deng
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Dong Li
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Jianhua Chen
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
| | - Yisheng Xu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Kai Zhang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Xiaona Shang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Qing Cao
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
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Li Y, Gong Q, Yang J, Feng Q, Song T, Wang W, Liu F. Hydrogen bond, ring tension and π-conjugation effects: methyl and vinyl substitutions dramatically change the photodynamics of Criegee intermediates. Phys Chem Chem Phys 2020; 22:15295-15302. [PMID: 32618986 DOI: 10.1039/d0cp01873b] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The substitution effect in chemistry is a concept that is probably too common to mention, while for a molecule with an elusive electronic structure, substitution can introduce an unusual effect that dramatically tunes the chemical process. To reveal the substitution effects on the photodynamics of Criegee Intermediates (CIs), we carried out the multireference CASSCF trajectory surface-hopping (TSH) molecular dynamics and CASPT2 electronic-structure calculations for a methyl-substituted CI (MCI) and a vinyl-substituted CI (VCI). The results show that for different substituents, the hydrogen bond, ring tension and π-conjugation not only alter the relative stabilities of the conformers/configurations, but also dramatically change the photo-induced channel of CIs. For an anti-MCI, the dominant channel starting from the S1 state is the ring-closure process leading to dioxirane, while in the syn configuration, the intramolecular CHO hydrogen bond hinders the rotation around the C-O bond and thus leads to a high yield of in-plane O-O dissociation towards acetaldehyde (X1A') and the O(1D) atom. In a VCI with an unsaturated substituent, the π-conjugation greatly strengthens the O-O bond and therefore no O-O dissociation is observed in all configurations. In addition, the CHO hydrogen bond in the syn(CO)-VCI further stabilizes the S1-state intermediates and makes them less reactive; in contrast, isomerization to dioxirane becomes the globally dominant channel in the anti(CO)-VCI. The dramatic substitution effects by saturated and unsaturated substituents on CIs found here will deepen the understanding of Criegee-intermediate chemistry.
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Affiliation(s)
- Yazhen Li
- Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an, Shaanxi 710062, P. R. China.
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Zhou X, Liu Y, Dong W, Yang X. Unimolecular Reaction Rate Measurement of syn-CH 3CHOO. J Phys Chem Lett 2019; 10:4817-4821. [PMID: 31382744 DOI: 10.1021/acs.jpclett.9b01740] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The unimolecular reactions of Criegee intermediates (CIs) are thought to be one of the significant sources of atmospheric OH radicals. However, stark discrepancies exist in the unimolecular reaction rate of the methyl-substituted CI CH3CHOO, typically from ozonolysis of alkenes such as trans-2-butene, between the results of ozonolysis of alkene experiments and the up-to-date theoretical calculations. That no further progress has been made since the method that directly produces CIs in the laboratory was developed is mostly attributed to the existence of two conformers, syn- and anti-CH3CHOO, and the methodological limitations of sensitive conformer-specific detection. We report a conformer-specific measurement of the unimolecular reaction rate of syn-CH3CHOO by using a high-repetition-rate laser-induced fluorescence method. At 298 K, the observed value of 182 ± 66 s-1 is in good agreement with recent theoretical calculations.
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Affiliation(s)
- Xiaohu Zhou
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- State Key Laboratory of Fine Chemicals and Key Laboratory of Industrial Ecology and Environmental Engineering, School of Environmental Science & Technology, Dalian University of Technology, Dalian 116024, China
| | - Yiqiang Liu
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Ministry of Education), School of Physics, Dalian University of Technology, Dalian 116024, China
| | - Wenrui Dong
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Xueming Yang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China
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