1
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Li B, Kumar M, Zhou C, Li L, Francisco JS. Mechanistic Insights into Criegee Intermediate-Hydroperoxyl Radical Chemistry. J Am Chem Soc 2022; 144:14740-14747. [PMID: 35921588 DOI: 10.1021/jacs.2c05346] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The reaction between a Criegee intermediate and the hydroperoxyl radical (HO2) is believed to play a role in the formation of new particles in the troposphere. Although the reaction has been previously studied in the gas phase, there are several knowledge gaps that still need to be filled. We simulated the reaction of anti-CH3CHOO with HO2 and HO2-H2O radical complexes in the gas phase at 0 K, which exhibited a low-barrier profile for water-containing systems and a barrierless profile for water-free systems. Moreover, the reaction was found to follow a proton-transfer mechanism, which challenges previous assumptions that the gas-phase reaction involves a hydrogen atom transfer. The HO2 radical was found to mediate the Criegee hydration reaction in the gas phase. Metadynamics simulations further confirmed that the expected radical adduct formation between anti-CH3CHOO and the HO2 radical, as well as the HO2- and H2O-mediated reactions in the gas phase, followed a concerted mechanism. By combining constrained ab initio molecular dynamics simulations with thermodynamic integration, we quantitively evaluated the free-energy barriers at high temperatures. The barriers obtained for all three Criegee-HO2 reaction systems were found to be temperature-dependent. We also compared the free-energy barriers of water-free and water-containing systems; the results revealed that water could hinder the reaction between the Criegee and HO2 radical. These results suggest that HO2 radicals may be involved in the formation of tropospheric radical adducts, and water molecules may also play important roles in the reactions of Criegee intermediates.
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Affiliation(s)
- Bai Li
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Manoj Kumar
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Chuan Zhou
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Lei Li
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Joseph S Francisco
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
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2
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Si H, Xiang T. Theoretical study of the radical–radical reactions between HOCH2OO and OH. Theor Chem Acc 2022. [DOI: 10.1007/s00214-022-02900-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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3
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Bai FY, Deng MS, Chen MY, Kong L, Ni S, Zhao Z, Pan XM. Atmospheric oxidation of fluoroalcohols initiated by ˙OH radicals in the presence of water and mineral dusts: mechanism, kinetics, and risk assessment. Phys Chem Chem Phys 2021; 23:13115-13127. [PMID: 34075970 DOI: 10.1039/d1cp01324f] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The transport and formation of fluorinated compounds are greatly significant due to their possible environmental risks. In this work, the ˙OH-mediated degradation of CF3CF2CF2CH2OH and CF3CHFCF2CH2OH in the presence of O2/NO/NO2 was studied by using density functional theory and the direct kinetic method. The formation mechanisms of perfluorocarboxylic/hydroperfluorocarboxylic acids (PFCAs/H-PFCAs), which were produced from the reactions of α-hydroxyperoxy radicals with NO/NO2 and the ensuing oxidation of α-hydroxyalkoxy radicals, were clarified and discussed. The roles of water and silica particles in the rate constants and ˙OH reaction mechanism with fluoroalcohols were investigated theoretically. The results showed that water and silica particles do not alter the reaction mechanism but obviously change the kinetic properties. Water could retard fluoroalcohol degradation by decreasing the rate constants by 3-5 orders of magnitude. However, the heterogeneous ˙OH-rate coefficients on the silica particle surfaces, including H4SiO4, H6Si2O7, and H12Si6O18, are larger than that of the naked reaction by 1.20-24.50 times. This finding suggested that these heterogeneous reactions may be responsible for the atmospheric loss of fluoroalcohols and the burden of PFCAs. In addition, fluoroalcohols could be exothermically trapped by H12Si6O18, H6Si2O7, and H4SiO4, in which the chemisorption on H12Si6O18 is stronger than that on H6Si2O7 or H4SiO4. The global warming potentials and radiative forcing of CF3CF2CF2CH2OH/CF3CHFCF2CH2OH were calculated to assess their contributions to the greenhouse effect. The toxicities of individual species were also estimated via the ECOSAR program and experimental measurements. This work enhances the understanding of the environmental formation of PFCAs and the transformation of fluoroalcohols.
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Affiliation(s)
- Feng-Yang Bai
- Institute of Catalysis for Energy and Environment, College of Chemistry and Chemical Engineering, Shenyang Normal University, Shenyang, Liaoning 110034, P. R. China.
| | - Ming-Shuai Deng
- Institute of Catalysis for Energy and Environment, College of Chemistry and Chemical Engineering, Shenyang Normal University, Shenyang, Liaoning 110034, P. R. China.
| | - Mei-Yan Chen
- Institute of Catalysis for Energy and Environment, College of Chemistry and Chemical Engineering, Shenyang Normal University, Shenyang, Liaoning 110034, P. R. China.
| | - Lian Kong
- Institute of Catalysis for Energy and Environment, College of Chemistry and Chemical Engineering, Shenyang Normal University, Shenyang, Liaoning 110034, P. R. China.
| | - Shuang Ni
- National & Local United Engineering Lab for Power Battery, Faculty of Chemistry, Northeast Normal University, Changchun 130024, P. R. China.
| | - Zhen Zhao
- Institute of Catalysis for Energy and Environment, College of Chemistry and Chemical Engineering, Shenyang Normal University, Shenyang, Liaoning 110034, P. R. China. and State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Chang Ping, Beijing 102249, P. R. China
| | - Xiu-Mei Pan
- National & Local United Engineering Lab for Power Battery, Faculty of Chemistry, Northeast Normal University, Changchun 130024, P. R. China.
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4
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Sandhiya L, Senthilkumar K. Unimolecular decomposition of acetyl peroxy radical: a potential source of tropospheric ketene. Phys Chem Chem Phys 2020; 22:26819-26827. [PMID: 33231595 DOI: 10.1039/d0cp04590j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The unimolecular decomposition of acetyl peroxy radicals followed by subsequent nitration is known to lead to the formation of peroxy acetyl nitrate (PAN) in the troposphere. Using high level quantum chemical calculations, we show that the acetyl peroxy radical is a precursor in the formation of tropospheric ketene. The results show that the presence of a single or double water molecule(s) as a catalyst does not influence the decomposition reaction directly to form ketene and hydroperoxy radicals. The electronic excitation of the reactive and product complexes occurs in the wavelength range of ∼1400 nm, suggesting that the complexes undergo photoexcitation in the near IR region. The results ascertain that the dissociation of acetyl peroxy radicals into ketene and hydroperoxy radicals occurs more likely through the excitation route and the corresponding excitation wavelength reveals that the reactions are red-light driven. Three different product complexes, ketene·HO2, ketene·H2O·HO2 and ketene·(H2O)2·HO2, are formed from the reaction. The direct dynamics simulations show that the product complexes are more stable and possess a long lifetime. The calculated temperature dependent equilibrium constant of the product complexes reveals that their atmospheric abundances decrease with increasing altitudes.
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Affiliation(s)
- L Sandhiya
- CSIR - National Institute of Science, Technology and Development Studies, New Delhi-110012, India.
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5
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Lu B, Song C, Liu J, Trabelsi T, Francisco JS, Wang L, Zeng X. Dihalogenated Methylperoxy Radicals: Spectroscopic Characterization and Photodecomposition by Release of HO .. Chemistry 2020; 26:2817-2820. [PMID: 31899574 DOI: 10.1002/chem.201905858] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Indexed: 11/08/2022]
Abstract
Two atmospherically relevant dihalogenated methylperoxy radicals CHX2 OO. (X=F and Cl) have been generated through O2 -oxidation of the corresponding alkyl radicals CHX2 . in the gas phase. The IR spectroscopic characterization of both radicals in cryogenic Ar- and N2 -matrices (15 K) is supported by 18 O-labeling and ab initio calculations at the UCCSD(T)/aug-cc-pVTZ level. Upon 266 nm laser irradiation, both radicals decompose mainly by releasing hydroxyl radicals (→HO. +X2 CO) via the intermediacy of intriguing α-hydroperoxyalkyl radicals (. CX2 OOH), implying that the photooxidation of dihalogenated hydrocarbons might serve as important sources of HO. radicals in the atmosphere.
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Affiliation(s)
- Bo Lu
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, P. R. China
| | - Chao Song
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, P. R. China
| | - Jie Liu
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, P. R. China
| | - Tarek Trabelsi
- Department of Earth and Environmental Science and Department of, Chemistry, University of Pennsylvania, Pennsylvania, 19104, USA
| | - Joseph S Francisco
- Department of Earth and Environmental Science and Department of, Chemistry, University of Pennsylvania, Pennsylvania, 19104, USA
| | - Lina Wang
- Department of Chemistry, Fudan University, Shanghai, 200433, P. R. China
| | - Xiaoqing Zeng
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, P. R. China.,Department of Chemistry, Fudan University, Shanghai, 200433, P. R. China
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6
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Zhong J, Kumar M, Anglada JM, Martins-Costa MTC, Ruiz-Lopez MF, Zeng XC, Francisco JS. Atmospheric Spectroscopy and Photochemistry at Environmental Water Interfaces. Annu Rev Phys Chem 2019; 70:45-69. [PMID: 31174459 DOI: 10.1146/annurev-physchem-042018-052311] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The air-water interface is ubiquitous in nature, as manifested in the form of the surfaces of oceans, lakes, and atmospheric aerosols. The aerosol interface, in particular, can play a crucial role in atmospheric chemistry. The adsorption of atmospheric species onto and into aerosols modifies their concentrations and chemistries. Moreover, the aerosol phase allows otherwise unlikely solution-phase chemistry to occur in the atmosphere. The effect of the air-water interface on these processes is not entirely known. This review summarizes recent theoretical investigations of the interactions of atmosphere species with the air-water interface, including reactant adsorption, photochemistry, and the spectroscopy of reactants at the water surface, with an emphasis on understanding differences between interfacial chemistries and the chemistries in both bulk solution and the gas phase. The results discussed here enable an understanding of fundamental concepts that lead to potential air-water interface effects, providing a framework to understand the effects of water surfaces on our atmosphere.
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Affiliation(s)
- J Zhong
- Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68566, USA
| | - M Kumar
- Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68566, USA
| | - J M Anglada
- Departament de Química Biològica i Modelització Molecular, Institut de Química Avançada de Catalunya-Consejo Superior de Investigaciones Cientificas (IQAC-CSIC), E-08034 Barcelona, Spain
| | - M T C Martins-Costa
- Le Laboratoire Structure et Réactivité des Systèmes Moléculaires Complexes (SRSMC), CNRS UMR 7019, Université de Lorraine, BP 70239, 54506 Vandoeuvre-lès-Nancy, France
| | - M F Ruiz-Lopez
- Le Laboratoire Structure et Réactivité des Systèmes Moléculaires Complexes (SRSMC), CNRS UMR 7019, Université de Lorraine, BP 70239, 54506 Vandoeuvre-lès-Nancy, France
| | - X C Zeng
- Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68566, USA
| | - Joseph S Francisco
- Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68566, USA.,Department of Earth and Environmental Science and Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6316, USA;
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7
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Bai FY, Ni S, Tang YZ, Pan XM, Zhao Z. New insights into 3M3M1B: the role of water in ˙OH-initiated degradation and aerosol formation in the presence of NOX (X = 1, 2) and an alkali. Phys Chem Chem Phys 2019; 21:17378-17392. [DOI: 10.1039/c9cp02793a] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Metal-free catalysis of the ˙OH-initiated degradation of 3M3M1B, nitrate aerosol formation, and peroxynitrate decomposition.
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Affiliation(s)
- Feng-Yang Bai
- Institute of Catalysis for Energy and Environment
- College of Chemistry and Chemical Engineering
- Shenyang Normal University
- Shenyang
- People's Republic of China
| | - Shuang Ni
- National & Local United Engineering Lab for Power Battery
- Faculty of Chemistry
- Northeast Normal University
- Changchun 130024
- People's Republic of China
| | - Yi-Zhen Tang
- School of Environmental and Municipal Engineering
- Qingdao Technological University
- Qingdao 266033
- People's Republic of China
| | - Xiu-Mei Pan
- National & Local United Engineering Lab for Power Battery
- Faculty of Chemistry
- Northeast Normal University
- Changchun 130024
- People's Republic of China
| | - Zhen Zhao
- Institute of Catalysis for Energy and Environment
- College of Chemistry and Chemical Engineering
- Shenyang Normal University
- Shenyang
- People's Republic of China
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8
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Zhang T, Wang K, Qiao Z, Zhang Y, Geng L, Wang R, Wang Z, Zhao C, Jin L. Catalytic effect of (H 2O) n ( n = 1-3) on the HO 2 + NH 2 → NH 3 + 3O 2 reaction under tropospheric conditions. RSC Adv 2018; 8:37105-37116. [PMID: 35557830 PMCID: PMC9089316 DOI: 10.1039/c8ra06549g] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Accepted: 10/23/2018] [Indexed: 11/29/2022] Open
Abstract
The effects of (H2O) n (n = 1-3) clusters on the HO2 + NH2 → NH3 + 3O2 reaction have been investigated by employing high-level quantum chemical calculations with M06-2X and CCSD(T) theoretical methods, and canonical variational transition (CVT) state theory with small curvature tunneling (SCT) correction. The calculated results show that two kinds of reaction, HO2⋯(H2O) n (n = 1-3) + NH2 and H2N⋯(H2O) n (n = 1-3) + HO2, are involved in the (H2O) n (n = 1-3) catalyzed HO2 + NH2 → NH3 + 3O2 reaction. Due to the fact that HO2⋯(H2O) n (n = 1-3) complexes have much larger stabilization energies and much higher concentrations than the corresponding complexes of H2N⋯(H2O) n (n = 1-3), the atmospheric relevance of the former reaction is more obvious with its effective rate constant of about 1-11 orders of magnitude faster than the corresponding latter reaction at 298 K. Meanwhile, due to the effective rate constant of the H2O⋯HO2 + NH2 reaction being respectively larger by 5-6 and 6-7 orders of magnitude than the corresponding reactions of HO2⋯(H2O)2 + NH2 and HO2⋯(H2O)3 + NH2, the catalytic effect of (H2O) n (n = 1-3) is mainly taken from the contribution of the water monomer. In addition, the enhancement factor of the water monomer is 10.06-13.30% within the temperature range of 275-320 K, which shows that at whole calculated temperatures, a positive water effect is obvious under atmospheric conditions.
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Affiliation(s)
- Tianlei Zhang
- Institute of Theoretical and Computational Chemistry, Shaanxi Key Laboratory of Catalysis, School of Chemical & Environment Science, Shaanxi University of Technology Hanzhong Shaanxi 723001 China +86-0916-2641083 +86-0916-2641083
| | - Kai Wang
- Institute of Theoretical and Computational Chemistry, Shaanxi Key Laboratory of Catalysis, School of Chemical & Environment Science, Shaanxi University of Technology Hanzhong Shaanxi 723001 China +86-0916-2641083 +86-0916-2641083
| | - Zhangyu Qiao
- Institute of Theoretical and Computational Chemistry, Shaanxi Key Laboratory of Catalysis, School of Chemical & Environment Science, Shaanxi University of Technology Hanzhong Shaanxi 723001 China +86-0916-2641083 +86-0916-2641083
| | - Yongqi Zhang
- Institute of Theoretical and Computational Chemistry, Shaanxi Key Laboratory of Catalysis, School of Chemical & Environment Science, Shaanxi University of Technology Hanzhong Shaanxi 723001 China +86-0916-2641083 +86-0916-2641083
| | - Lin Geng
- Institute of Theoretical and Computational Chemistry, Shaanxi Key Laboratory of Catalysis, School of Chemical & Environment Science, Shaanxi University of Technology Hanzhong Shaanxi 723001 China +86-0916-2641083 +86-0916-2641083
| | - Rui Wang
- Institute of Theoretical and Computational Chemistry, Shaanxi Key Laboratory of Catalysis, School of Chemical & Environment Science, Shaanxi University of Technology Hanzhong Shaanxi 723001 China +86-0916-2641083 +86-0916-2641083
| | - Zhiyin Wang
- Institute of Theoretical and Computational Chemistry, Shaanxi Key Laboratory of Catalysis, School of Chemical & Environment Science, Shaanxi University of Technology Hanzhong Shaanxi 723001 China +86-0916-2641083 +86-0916-2641083
| | - Caibin Zhao
- Institute of Theoretical and Computational Chemistry, Shaanxi Key Laboratory of Catalysis, School of Chemical & Environment Science, Shaanxi University of Technology Hanzhong Shaanxi 723001 China +86-0916-2641083 +86-0916-2641083
| | - Linxia Jin
- Institute of Theoretical and Computational Chemistry, Shaanxi Key Laboratory of Catalysis, School of Chemical & Environment Science, Shaanxi University of Technology Hanzhong Shaanxi 723001 China +86-0916-2641083 +86-0916-2641083
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9
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Wu Z, Xu J, Deng G, Chu X, Sokolenko L, Trabelsi T, Francisco JS, Eckhardt AK, Schreiner PR, Zeng X. The Trifluoromethyl Sulfinyl and Oxathiyl Radicals. Chemistry 2017; 24:1505-1508. [DOI: 10.1002/chem.201705142] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Indexed: 11/07/2022]
Affiliation(s)
- Zhuang Wu
- College of Chemistry, Chemical Engineering and Materials Science; Soochow University; Suzhou 215123 P.R. China
| | - Jian Xu
- College of Chemistry, Chemical Engineering and Materials Science; Soochow University; Suzhou 215123 P.R. China
| | - Guohai Deng
- College of Chemistry, Chemical Engineering and Materials Science; Soochow University; Suzhou 215123 P.R. China
| | - Xianxu Chu
- College of Chemistry, Chemical Engineering and Materials Science; Soochow University; Suzhou 215123 P.R. China
| | - Liubov Sokolenko
- Organofluorine Chemistry Department, Institute of Organic Chemistry; National Academy of Sciences of Ukraine; Kiev-94 02660 Ukraine
| | - Tarek Trabelsi
- University of Nebraska-Lincoln; Lincoln Nebraska 68526 USA
| | - Joseph S. Francisco
- Department of Chemistry; Purdue University; West Lafayette Indiana 47907 USA
| | - André K. Eckhardt
- Institute of Organic Chemistry; Justus-Liebig University; Heinrich-Buff-Ring 17 35392 Giessen Germany
| | - Peter R. Schreiner
- Institute of Organic Chemistry; Justus-Liebig University; Heinrich-Buff-Ring 17 35392 Giessen Germany
| | - Xiaoqing Zeng
- College of Chemistry, Chemical Engineering and Materials Science; Soochow University; Suzhou 215123 P.R. China
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10
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Chen L, Huang Y, Xue Y, Cao J, Wang W. Competition between HO2 and H2O2 Reactions with CH2OO/anti-CH3CHOO in the Oligomer Formation: A Theoretical Perspective. J Phys Chem A 2017; 121:6981-6991. [DOI: 10.1021/acs.jpca.7b05951] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Long Chen
- Key Lab of Aerosol Chemistry & Physics, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an, Shaanxi 710061, China
- State
Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an, Shaanxi 710061, China
| | - Yu Huang
- Key Lab of Aerosol Chemistry & Physics, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an, Shaanxi 710061, China
- State
Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an, Shaanxi 710061, China
| | - Yonggang Xue
- Key Lab of Aerosol Chemistry & Physics, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an, Shaanxi 710061, China
- State
Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an, Shaanxi 710061, China
| | - Junji Cao
- Key Lab of Aerosol Chemistry & Physics, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an, Shaanxi 710061, China
- State
Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an, Shaanxi 710061, China
| | - Wenliang Wang
- School
of Chemistry and Chemical Engineering, Key Laboratory for Macromolecular
Science of Shaanxi Province, Shaanxi Normal University, Xi’an, Shaanxi 710119, China
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11
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Abstract
Elemental sulfur aerosols are ubiquitous in the atmospheres of Venus, ancient Earth, and Mars. There is now an evolving body of evidence suggesting that these aerosols have also played a role in the evolution of early life on Earth. However, the exact details of their formation mechanism remain an open question. The present theoretical calculations suggest a chemical mechanism that takes advantage of the interaction between sulfur oxides, SOn (n = 1, 2, 3) and hydrogen sulfide (nH2S), resulting in the efficient formation of a Sn+1 particle. Interestingly, the SOn + nH2S → Sn+1 + nH2O reactions occur via low-energy pathways under water or sulfuric acid catalysis. Once the Sn+1 particles are formed, they may further nucleate to form larger polysulfur aerosols, thus providing a chemical framework for understanding the formation mechanism of S0 aerosols in different environments.
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Affiliation(s)
- Manoj Kumar
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln, NE 68588
| | - Joseph S Francisco
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln, NE 68588
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12
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Cedrowski J, Litwinienko G, Baschieri A, Amorati R. Hydroperoxyl Radicals (HOO.
): Vitamin E Regeneration and H-Bond Effects on the Hydrogen Atom Transfer. Chemistry 2016; 22:16441-16445. [DOI: 10.1002/chem.201603722] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Indexed: 01/07/2023]
Affiliation(s)
- Jakub Cedrowski
- Faculty of Chemistry; University of Warsaw; Pasteura 1 02-093 Warsaw Poland
| | | | - Andrea Baschieri
- Department of Chemistry “G. Ciamician”; University of Bologna; Via S. Giacomo 11 40126 Bologna Italy
| | - Riccardo Amorati
- Department of Chemistry “G. Ciamician”; University of Bologna; Via S. Giacomo 11 40126 Bologna Italy
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13
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Kumar M, Sinha A, Francisco JS. Role of Double Hydrogen Atom Transfer Reactions in Atmospheric Chemistry. Acc Chem Res 2016; 49:877-83. [PMID: 27074637 DOI: 10.1021/acs.accounts.6b00040] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Hydrogen atom transfer (HAT) reactions are ubiquitous and play a crucial role in chemistries occurring in the atmosphere, biology, and industry. In the atmosphere, the most common and traditional HAT reaction is that associated with the OH radical abstracting a hydrogen atom from the plethora of organic molecules in the troposphere via R-H + OH → R + H2O. This reaction motif involves a single hydrogen transfer. More recently, in the literature, there is an emerging framework for a new class of HAT reactions that involves double hydrogen transfers. These reactions are broadly classified into four categories: (i) addition, (ii) elimination, (iii) substitution, and (iv) rearrangement. Hydration and dehydration are classic examples of addition and elimination reactions, respectively whereas tautomerization or isomerization belongs to a class of rearrangement reactions. Atmospheric acids and water typically mediate these reactions. Organic and inorganic acids are present in appreciable levels in the atmosphere and are capable of facilitating two-point hydrogen bonding interactions with oxygenates possessing an hydroxyl and/or carbonyl-type functionality. As a result, acids influence the reactivity of oxygenates and, thus, the energetics and kinetics of their HAT-based chemistries. The steric and electronic effects of acids play an important role in determining the efficacy of acid catalysis. Acids that reduce the steric strain of 1:1 substrate···acid complex are generally better catalysts. Among a family of monocarboxylic acids, the electronic effects become important; barrier to the catalyzed reaction correlates strongly with the pKa of the acid. Under acid catalysis, the hydration of carbonyl compounds leads to the barrierless formation of diols, which can serve as seed particles for atmospheric aerosol growth. The hydration of sulfur trioxide, which is the principle mechanism for atmospheric sulfuric acid formation, also becomes barrierless under acid catalysis. Rate calculations suggest that such acid catalysis play a key role in the formation of sulfuric acid in the Earth's stratosphere, Venusian atmosphere, and on heterogeneous surfaces. Over the past few years, theoretical calculations have shown that these acid-mediated double hydrogen atom transfers are important in the chemistry of Earth's atmosphere as well as that of other planets. This Account reviews and puts into perspective some of these atmospheric HAT reactions and their environmental significance.
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Affiliation(s)
- Manoj Kumar
- Department
of Chemistry, University of Nebraska—Lincoln, Lincoln, Nebraska 68588, United States
| | - Amitabha Sinha
- Department
of Chemistry and Biochemistry, University of California—San Diego, La Jolla, California 92093-0314, United States
| | - Joseph S. Francisco
- Department
of Chemistry, University of Nebraska—Lincoln, Lincoln, Nebraska 68588, United States
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14
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Kumar M, Francisco JS. Red-Light Initiated Decomposition of α-Hydroxy Methylperoxy Radical in the Presence of Organic and Inorganic Acids: Implications for the HOx Formation in the Lower Stratosphere. J Phys Chem A 2016; 120:2677-83. [DOI: 10.1021/acs.jpca.6b01515] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Manoj Kumar
- Department of Chemistry, University of Nebraska—Lincoln, 639 North 12th Street, Lincoln, Nebraska 68588, United States
| | - Joseph S. Francisco
- Department of Chemistry, University of Nebraska—Lincoln, 639 North 12th Street, Lincoln, Nebraska 68588, United States
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