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Liu L, Zhang C, Xia Y, Zhang W, Wang Z, Tang X. Dimeric product formation in the self-reaction of small peroxy radicals using synchrotron radiation vacuum ultraviolet photoionization mass spectrometry. CHEMOSPHERE 2024; 363:142846. [PMID: 39025306 DOI: 10.1016/j.chemosphere.2024.142846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2024] [Revised: 07/11/2024] [Accepted: 07/12/2024] [Indexed: 07/20/2024]
Abstract
Peroxy radicals (RO2) are key reactive intermediates in atmospheric oxidation processes and yet their chemistry is not fully unraveled. Little is known about their structures and the structures of the dimeric products (ROOR) in the self-reaction of small RO2, which are among the most abundant RO2 in the atmosphere. The product branching ratios of ROOR and their atmospheric roles are still in controversy. Here, the self-reaction of propyl peroxy radicals (C3H7O2), a typical small RO2 radical in the atmosphere, has been studied using synchrotron radiation vacuum ultraviolet photoionization mass spectrometry. Both radical (C3H7O) and closed-shell molecular (C3H6O, C3H7OH, C3H7OOC3H7) products in the self-reaction are observed in photoionization mass spectra and their elusive isomers are definitely identified in mass-selected photoionization spectra. Three isomers of the C3H7OOC3H7 dimeric products, R1OOR1, R1OOR2, and R2OOR2 (R1 and R2 represent 1-C3H7 and 2-C3H7, respectively), as well as their complex structures have been determined for the first time. Kinetic experiments are performed and compared with chemical simulations to reveal the sources of specific products. The branching ratio of the C3H7OOC3H7 dimeric channel is measured at 10 ± 5%. This work demonstrates that the dimeric product formation in the self-reaction of small RO2 radicals is non-negligible and should provide valuable new insight into atmospheric modelling.
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Affiliation(s)
- Lingyu Liu
- Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, 230031, Anhui, China; School of Environmental Science and Optoelectronic Technology, University of Science and Technology of China, Hefei, 230026, Anhui, China
| | - Cuihong Zhang
- Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, 230031, Anhui, China
| | - Yu Xia
- Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, 230031, Anhui, China; Science Island Branch, Graduate School, University of Science and Technology of China, Hefei, 230026, Anhui, China
| | - Weijun Zhang
- Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, 230031, Anhui, China; School of Environmental Science and Optoelectronic Technology, University of Science and Technology of China, Hefei, 230026, Anhui, China.
| | - Zhandong Wang
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230029, Anhui, China
| | - Xiaofeng Tang
- Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, 230031, Anhui, China.
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2
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Chen C, Chen YX, Zhang CJ. A Radical-Generating Probe to Release Free Fluorophores and Identify Artemisinin-Sensitive Cancer Cells. ACS Sens 2024; 9:2310-2316. [PMID: 38651676 DOI: 10.1021/acssensors.4c00010] [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] [Indexed: 04/25/2024]
Abstract
The smart light-up probes have been extensively developed to image various enzymes and other bioactive molecules. Upon activation, these probes result in light-up fluorophores that exist in a protein-bound or a free form. The difference between these two forms has not yet been reported. Here, we present a pair of smart light-up probes that generate a protein-bound fluorophore and a free fluorophore upon activation by heme. Probe 8 generated a radical-attached fluorophore that predominantly existed in the free form, while probe 10 generated an α,β-unsaturated ketone-attached fluorophore that showed extensive labeling of proteins. In live-cell imaging, probe 8 showed greater fluorescence intensity than probe 10 when low concentrations (0.1-5 μM) of the probes were used, but probe 8 was less fluorescent than probe 10 when the concentrations of the probes were high (10 μM). Finally, probe 8 was used to reflect the activation level of the endoperoxide bond in cancer cells and to effectively distinguish ART-sensitive cancer cells from ART-insensitive ones.
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Affiliation(s)
- Chen Chen
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Beijing Key Laboratory of Active Substance Discovery and Druggability Evaluation, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Yi-Xin Chen
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Beijing Key Laboratory of Active Substance Discovery and Druggability Evaluation, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Chong-Jing Zhang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Beijing Key Laboratory of Active Substance Discovery and Druggability Evaluation, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
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3
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Pasik D, Frandsen BN, Meder M, Iyer S, Kurtén T, Myllys N. Gas-Phase Oxidation of Atmospherically Relevant Unsaturated Hydrocarbons by Acyl Peroxy Radicals. J Am Chem Soc 2024; 146:13427-13437. [PMID: 38712858 DOI: 10.1021/jacs.4c02523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
This study assesses the atmospheric impact of reactions between unsaturated hydrocarbons such as isoprene and monoterpenes and peroxy radicals containing various functional groups. We find that reactions between alkenes and acyl peroxy radicals have reaction rates high enough to be feasible in the atmosphere and lead to high molar mass accretion products. Moreover, the reaction between unsaturated hydrocarbons and acyl peroxy radicals leads to an alkyl radical, to which molecular oxygen rapidly adds. This finding is confirmed by both theoretical calculations and experiments. The formed perester peroxy radical may either undergo further H-shift reactions or react bimolecularly. The multifunctional oxygenated compounds formed through acyl peroxy radical + alkene reactions are potentially important contributors to particle formation and growth. Thus, acyl peroxy radical-initiated oxidation chemistry may need to be included in atmospheric models.
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Affiliation(s)
- Dominika Pasik
- Department of Chemistry, University of Helsinki, Helsinki 00014, Finland
- Institute for Atmospheric and Earth System Research, University of Helsinki, Helsinki 00014, Finland
| | - Benjamin N Frandsen
- Department of Chemistry, University of Helsinki, Helsinki 00014, Finland
- Aerosol Physics Laboratory, Tampere University, Tampere 33014, Finland
| | - Melissa Meder
- Institute for Atmospheric and Earth System Research, University of Helsinki, Helsinki 00014, Finland
| | - Siddharth Iyer
- Aerosol Physics Laboratory, Tampere University, Tampere 33014, Finland
| | - Theo Kurtén
- Department of Chemistry, University of Helsinki, Helsinki 00014, Finland
- Institute for Atmospheric and Earth System Research, University of Helsinki, Helsinki 00014, Finland
| | - Nanna Myllys
- Department of Chemistry, University of Helsinki, Helsinki 00014, Finland
- Institute for Atmospheric and Earth System Research, University of Helsinki, Helsinki 00014, Finland
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4
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Sandström H, Rissanen M, Rousu J, Rinke P. Data-Driven Compound Identification in Atmospheric Mass Spectrometry. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2306235. [PMID: 38095508 PMCID: PMC10885664 DOI: 10.1002/advs.202306235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 11/04/2023] [Indexed: 02/24/2024]
Abstract
Aerosol particles found in the atmosphere affect the climate and worsen air quality. To mitigate these adverse impacts, aerosol particle formation and aerosol chemistry in the atmosphere need to be better mapped out and understood. Currently, mass spectrometry is the single most important analytical technique in atmospheric chemistry and is used to track and identify compounds and processes. Large amounts of data are collected in each measurement of current time-of-flight and orbitrap mass spectrometers using modern rapid data acquisition practices. However, compound identification remains a major bottleneck during data analysis due to lacking reference libraries and analysis tools. Data-driven compound identification approaches could alleviate the problem, yet remain rare to non-existent in atmospheric science. In this perspective, the authors review the current state of data-driven compound identification with mass spectrometry in atmospheric science and discuss current challenges and possible future steps toward a digital era for atmospheric mass spectrometry.
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Affiliation(s)
- Hilda Sandström
- Department of Applied Physics, Aalto University, P.O. Box 11000, FI-00076, Aalto, Espoo, Finland
| | - Matti Rissanen
- Aerosol Physics Laboratory, Tampere University, FI-33720, Tampere, Finland
- Department of Chemistry, University of Helsinki, P.O. Box 55, A.I. Virtasen aukio 1, FI-00560, Helsinki, Finland
| | - Juho Rousu
- Department of Computer Science, Aalto University, P.O. Box 11000, FI-00076, Aalto, Espoo, Finland
| | - Patrick Rinke
- Department of Applied Physics, Aalto University, P.O. Box 11000, FI-00076, Aalto, Espoo, Finland
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5
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Li D, Huang W, Wang D, Wang M, Thornton JA, Caudillo L, Rörup B, Marten R, Scholz W, Finkenzeller H, Marie G, Baltensperger U, Bell DM, Brasseur Z, Curtius J, Dada L, Duplissy J, Gong X, Hansel A, He XC, Hofbauer V, Junninen H, Krechmer JE, Kürten A, Lamkaddam H, Lehtipalo K, Lopez B, Ma Y, Mahfouz NGA, Manninen HE, Mentler B, Perrier S, Petäjä T, Pfeifer J, Philippov M, Schervish M, Schobesberger S, Shen J, Surdu M, Tomaz S, Volkamer R, Wang X, Weber SK, Welti A, Worsnop DR, Wu Y, Yan C, Zauner-Wieczorek M, Kulmala M, Kirkby J, Donahue NM, George C, El-Haddad I, Bianchi F, Riva M. Nitrate Radicals Suppress Biogenic New Particle Formation from Monoterpene Oxidation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:1601-1614. [PMID: 38185880 DOI: 10.1021/acs.est.3c07958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Highly oxygenated organic molecules (HOMs) are a major source of new particles that affect the Earth's climate. HOM production from the oxidation of volatile organic compounds (VOCs) occurs during both the day and night and can lead to new particle formation (NPF). However, NPF involving organic vapors has been reported much more often during the daytime than during nighttime. Here, we show that the nitrate radicals (NO3), which arise predominantly at night, inhibit NPF during the oxidation of monoterpenes based on three lines of observational evidence: NPF experiments in the CLOUD (Cosmics Leaving OUtdoor Droplets) chamber at CERN (European Organization for Nuclear Research), radical chemistry experiments using an oxidation flow reactor, and field observations in a wetland that occasionally exhibits nocturnal NPF. Nitrooxy-peroxy radicals formed from NO3 chemistry suppress the production of ultralow-volatility organic compounds (ULVOCs) responsible for biogenic NPF, which are covalently bound peroxy radical (RO2) dimer association products. The ULVOC yield of α-pinene in the presence of NO3 is one-fifth of that resulting from ozone chemistry alone. Even trace amounts of NO3 radicals, at sub-parts per trillion level, suppress the NPF rate by a factor of 4. Ambient observations further confirm that when NO3 chemistry is involved, monoterpene NPF is completely turned off. Our results explain the frequent absence of nocturnal biogenic NPF in monoterpene (α-pinene)-rich environments.
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Affiliation(s)
- Dandan Li
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, Villeurbanne 69626, France
| | - Wei Huang
- Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki 00014, Finland
| | - Dongyu Wang
- Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, Villigen 5232, Switzerland
| | - Mingyi Wang
- Center for Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Joel A Thornton
- Department of Atmospheric Sciences, University of Washington, Seattle, Washington 98195, United States
| | - Lucía Caudillo
- Institute for Atmospheric and Environmental Sciences, Goethe University Frankfurt, Frankfurt am Main 60438, Germany
| | - Birte Rörup
- Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki 00014, Finland
| | - Ruby Marten
- Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, Villigen 5232, Switzerland
| | - Wiebke Scholz
- Institute for Ion Physics and Applied Physics, University of Innsbruck, Innsbruck 6020, Austria
| | - Henning Finkenzeller
- Department of Chemistry & CIRES, University of Colorado Boulder, Boulder, Colorado 80309, United States
| | - Guillaume Marie
- Institute for Atmospheric and Environmental Sciences, Goethe University Frankfurt, Frankfurt am Main 60438, Germany
| | - Urs Baltensperger
- Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, Villigen 5232, Switzerland
| | - David M Bell
- Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, Villigen 5232, Switzerland
| | - Zoé Brasseur
- Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki 00014, Finland
| | - Joachim Curtius
- Institute for Atmospheric and Environmental Sciences, Goethe University Frankfurt, Frankfurt am Main 60438, Germany
| | - Lubna Dada
- Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, Villigen 5232, Switzerland
| | - Jonathan Duplissy
- Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki 00014, Finland
- Helsinki Institute of Physics (HIP)/Physics, Faculty of Science, University of Helsinki, Helsinki 00014, Finland
| | - Xianda Gong
- Leibniz Institute for Tropospheric Research, Leipzig 04318, Germany
| | - Armin Hansel
- Institute for Ion Physics and Applied Physics, University of Innsbruck, Innsbruck 6020, Austria
| | - Xu-Cheng He
- Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki 00014, Finland
| | - Victoria Hofbauer
- Center for Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Heikki Junninen
- Institute of Physics, University of Tartu, Tartu 50090, Estonia
| | - Jordan E Krechmer
- Aerodyne Research Inc., Billerica, Massachusetts 01821, United States
| | - Andreas Kürten
- Institute for Atmospheric and Environmental Sciences, Goethe University Frankfurt, Frankfurt am Main 60438, Germany
| | - Houssni Lamkaddam
- Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, Villigen 5232, Switzerland
| | - Katrianne Lehtipalo
- Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki 00014, Finland
- Finnish Meteorological Institute, Helsinki 00560, Finland
| | - Brandon Lopez
- Center for Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Yingge Ma
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environment Sciences, Shanghai 200233, P. R. China
| | - Naser G A Mahfouz
- Atmospheric and Oceanic Sciences, Princeton University, Princeton, New Jersey 08540, United States
| | - Hanna E Manninen
- CERN, the European Organization for Nuclear Research, Geneve 23 CH-1211, Switzerland
| | - Bernhard Mentler
- Institute for Ion Physics and Applied Physics, University of Innsbruck, Innsbruck 6020, Austria
| | - Sebastien Perrier
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, Villeurbanne 69626, France
| | - Tuukka Petäjä
- Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki 00014, Finland
| | - Joschka Pfeifer
- CERN, the European Organization for Nuclear Research, Geneve 23 CH-1211, Switzerland
| | - Maxim Philippov
- P.N. Lebedev Physical Institute of the Russian Academy of Sciences, Moscow 119991, Russia
| | - Meredith Schervish
- Center for Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | | | - Jiali Shen
- Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki 00014, Finland
| | - Mihnea Surdu
- Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, Villigen 5232, Switzerland
| | - Sophie Tomaz
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, Villeurbanne 69626, France
| | - Rainer Volkamer
- Department of Chemistry & CIRES, University of Colorado Boulder, Boulder, Colorado 80309, United States
| | - Xinke Wang
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, Villeurbanne 69626, France
| | - Stefan K Weber
- Institute for Atmospheric and Environmental Sciences, Goethe University Frankfurt, Frankfurt am Main 60438, Germany
- CERN, the European Organization for Nuclear Research, Geneve 23 CH-1211, Switzerland
| | - André Welti
- Finnish Meteorological Institute, Helsinki 00560, Finland
| | - Douglas R Worsnop
- Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki 00014, Finland
- Aerodyne Research Inc., Billerica, Massachusetts 01821, United States
| | - Yusheng Wu
- Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki 00014, Finland
| | - Chao Yan
- Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki 00014, Finland
| | - Marcel Zauner-Wieczorek
- Institute for Atmospheric and Environmental Sciences, Goethe University Frankfurt, Frankfurt am Main 60438, Germany
| | - Markku Kulmala
- Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki 00014, Finland
| | - Jasper Kirkby
- Institute for Atmospheric and Environmental Sciences, Goethe University Frankfurt, Frankfurt am Main 60438, Germany
- CERN, the European Organization for Nuclear Research, Geneve 23 CH-1211, Switzerland
| | - Neil M Donahue
- Center for Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Christian George
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, Villeurbanne 69626, France
| | - Imad El-Haddad
- Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, Villigen 5232, Switzerland
| | - Federico Bianchi
- Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki 00014, Finland
| | - Matthieu Riva
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, Villeurbanne 69626, France
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6
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Shao X, Wu Z, Wang L, Rauhut G, Zeng X. Identification and Photochemistry of the Mercaptomethyl Radical. J Phys Chem Lett 2023; 14:10450-10456. [PMID: 37962268 DOI: 10.1021/acs.jpclett.3c02526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
The mercaptomethyl radical (·CH2SH) is a higher-energy isomer of the methylthio radical (CH3S·) that has been proposed as an important intermediate in atmospheric and interstellar sulfur chemistry. Herein, we report the spectroscopic identification of ·CH2SH during the UV (365 nm) photolysis of CH3S· in a solid Ar-matrix at 10 K. Upon subsequent irradiation at 266 nm, the dehydrogenation of ·CH2SH to yield CS via the intermediacy of the elusive thioformyl radical (HCS·) has also been observed. The characterization of ·CH2SH and HCS· with matrix-isolation IR and UV-vis spectroscopy is supported by 13C-isotope labeling and quantum chemical calculations at the CCSD(T)-F12a/cc-pVTZ-F12 level using configuration-selective vibrational configuration interaction theory (VCI). The disclosed photochemistry of ·CH2SH provides new insight into understanding the chemical evolution of organosulfur molecules in the interstellar medium (ISM).
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Affiliation(s)
- Xin Shao
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai 200433, China
| | - Zhuang Wu
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai 200433, China
| | - Lina Wang
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai 200433, China
| | - Guntram Rauhut
- Institute for Theoretical Chemistry, University of Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany
| | - Xiaoqing Zeng
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai 200433, China
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7
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Yue H, Zhang C, Lin X, Wen Z, Zhang W, Mostafa S, Luo PL, Zhang Z, Hemberger P, Fittschen C, Tang X. Dimeric Product of Peroxy Radical Self-Reaction Probed with VUV Photoionization Mass Spectrometry and Theoretical Calculations: The Case of C 2H 5OOC 2H 5. Int J Mol Sci 2023; 24:ijms24043731. [PMID: 36835141 PMCID: PMC9965172 DOI: 10.3390/ijms24043731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 02/06/2023] [Accepted: 02/10/2023] [Indexed: 02/16/2023] Open
Abstract
Organic peroxy radicals (RO2) as key intermediates in tropospheric chemistry exert a controlling influence on the cycling of atmospheric reactive radicals and the production of secondary pollutants, such as ozone and secondary organic aerosols (SOA). Herein, we present a comprehensive study of the self-reaction of ethyl peroxy radicals (C2H5O2) by using advanced vacuum ultraviolet (VUV) photoionization mass spectrometry in combination with theoretical calculations. A VUV discharge lamp in Hefei and synchrotron radiation at the Swiss Light Source (SLS) are employed as the photoionization light sources, combined with a microwave discharge fast flow reactor in Hefei and a laser photolysis reactor at the SLS. The dimeric product, C2H5OOC2H5, as well as other products, CH3CHO, C2H5OH and C2H5O, formed from the self-reaction of C2H5O2 are clearly observed in the photoionization mass spectra. Two kinds of kinetic experiments have been performed in Hefei by either changing the reaction time or the initial concentration of C2H5O2 radicals to confirm the origins of the products and to validate the reaction mechanisms. Based on the fitting of the kinetic data with the theoretically calculated results and the peak area ratios in the photoionization mass spectra, a branching ratio of 10 ± 5% for the pathway leading to the dimeric product C2H5OOC2H5 is measured. In addition, the adiabatic ionization energy (AIE) of C2H5OOC2H5 is determined at 8.75 ± 0.05 eV in the photoionization spectrum with the aid of Franck-Condon calculations and its structure is revealed here for the first time. The potential energy surface of the C2H5O2 self-reaction has also been theoretically calculated with a high-level of theory to understand the reaction processes in detail. This study provides a new insight into the direct measurement of the elusive dimeric product ROOR and demonstrates its non-negligible branching ratio in the self-reaction of small RO2 radicals.
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Affiliation(s)
- Hao Yue
- Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
- Science Island Branch, Graduate School, University of Science and Technology of China, Hefei 230026, China
| | - Cuihong Zhang
- Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
- Science Island Branch, Graduate School, University of Science and Technology of China, Hefei 230026, China
- Univ. Lille, CNRS, UMR 8522-PC2A–Physicochimie des Processus de Combustion et de I’Atmosphère, F-59000 Lille, France
| | - Xiaoxiao Lin
- Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
| | - Zuoying Wen
- Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
| | - Weijun Zhang
- Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
| | - Sabah Mostafa
- Univ. Lille, CNRS, UMR 8522-PC2A–Physicochimie des Processus de Combustion et de I’Atmosphère, F-59000 Lille, France
| | - Pei-Ling Luo
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan
| | - Zihao Zhang
- Laboratory for Synchrotron Radiation and Femtochemistry, Paul Scherrer Institute, CH-5232 Villigen, Switzerland
| | - Patrick Hemberger
- Laboratory for Synchrotron Radiation and Femtochemistry, Paul Scherrer Institute, CH-5232 Villigen, Switzerland
| | - Christa Fittschen
- Univ. Lille, CNRS, UMR 8522-PC2A–Physicochimie des Processus de Combustion et de I’Atmosphère, F-59000 Lille, France
- Correspondence: (C.F.); (X.T.)
| | - Xiaofeng Tang
- Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
- Correspondence: (C.F.); (X.T.)
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8
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Zádor J, Martí C, Van de Vijver R, Johansen SL, Yang Y, Michelsen HA, Najm HN. Automated Reaction Kinetics of Gas-Phase Organic Species over Multiwell Potential Energy Surfaces. J Phys Chem A 2023; 127:565-588. [PMID: 36607817 DOI: 10.1021/acs.jpca.2c06558] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Automation of rate-coefficient calculations for gas-phase organic species became possible in recent years and has transformed how we explore these complicated systems computationally. Kinetics workflow tools bring rigor and speed and eliminate a large fraction of manual labor and related error sources. In this paper we give an overview of this quickly evolving field and illustrate, through five detailed examples, the capabilities of our own automated tool, KinBot. We bring examples from combustion and atmospheric chemistry of C-, H-, O-, and N-atom-containing species that are relevant to molecular weight growth and autoxidation processes. The examples shed light on the capabilities of automation and also highlight particular challenges associated with the various chemical systems that need to be addressed in future work.
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Affiliation(s)
- Judit Zádor
- Combustion Research Facility, Sandia National Laboratories, Livermore94550, California, United States
| | - Carles Martí
- Combustion Research Facility, Sandia National Laboratories, Livermore94550, California, United States
| | | | - Sommer L Johansen
- Combustion Research Facility, Sandia National Laboratories, Livermore94550, California, United States
| | - Yoona Yang
- Combustion Research Facility, Sandia National Laboratories, Livermore94550, California, United States
| | - Hope A Michelsen
- Department of Mechanical Engineering, University of Colorado Boulder, Boulder80309, Colorado, United States
| | - Habib N Najm
- Combustion Research Facility, Sandia National Laboratories, Livermore94550, California, United States
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9
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Wang S, Zhao Y, Chan AWH, Yao M, Chen Z, Abbatt JPD. Organic Peroxides in Aerosol: Key Reactive Intermediates for Multiphase Processes in the Atmosphere. Chem Rev 2023; 123:1635-1679. [PMID: 36630720 DOI: 10.1021/acs.chemrev.2c00430] [Citation(s) in RCA: 21] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Organic peroxides (POs) are organic molecules with one or more peroxide (-O-O-) functional groups. POs are commonly regarded as chemically labile termination products from gas-phase radical chemistry and therefore serve as temporary reservoirs for oxidative radicals (HOx and ROx) in the atmosphere. Owing to their ubiquity, active gas-particle partitioning behavior, and reactivity, POs are key reactive intermediates in atmospheric multiphase processes determining the life cycle (formation, growth, and aging), climate, and health impacts of aerosol. However, there remain substantial gaps in the origin, molecular diversity, and fate of POs due to their complex nature and dynamic behavior. Here, we summarize the current understanding on atmospheric POs, with a focus on their identification and quantification, state-of-the-art analytical developments, molecular-level formation mechanisms, multiphase chemical transformation pathways, as well as environmental and health impacts. We find that interactions with SO2 and transition metal ions are generally the fast PO transformation pathways in atmospheric liquid water, with lifetimes estimated to be minutes to hours, while hydrolysis is particularly important for α-substituted hydroperoxides. Meanwhile, photolysis and thermolysis are likely minor sinks for POs. These multiphase PO transformation pathways are distinctly different from their gas-phase fates, such as photolysis and reaction with OH radicals, which highlights the need to understand the multiphase partitioning of POs. By summarizing the current advances and remaining challenges for the investigation of POs, we propose future research priorities regarding their origin, fate, and impacts in the atmosphere.
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Affiliation(s)
- Shunyao Wang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai200240, China
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai200444, China
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, OntarioM5S 3E5, Canada
| | - Yue Zhao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai200240, China
| | - Arthur W H Chan
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, OntarioM5S 3E5, Canada
- School of the Environment, University of Toronto, Toronto, OntarioM5S 3E8, Canada
| | - Min Yao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai200240, China
| | - Zhongming Chen
- State Key Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing100871, China
| | - Jonathan P D Abbatt
- Department of Chemistry, University of Toronto, Toronto, OntarioM5S 3H6, Canada
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10
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Gao Y, Lu K, Zhang Y. Review of technologies and their applications for the speciated detection of RO 2 radicals. J Environ Sci (China) 2023; 123:487-499. [PMID: 36522008 DOI: 10.1016/j.jes.2022.09.028] [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: 03/10/2022] [Revised: 09/17/2022] [Accepted: 09/19/2022] [Indexed: 06/17/2023]
Abstract
Peroxy radicals (RO2), which are formed during the oxidation of volatile organic compounds, play an important role in atmospheric oxidation reactions. Therefore, the measurement of RO2, especially distinct species of RO2 radicals, is important and greatly helps the exploration of atmospheric chemistry mechanisms. Although the speciated detection of RO2 radicals remains challenging, various methods have been developed to study them in detail. These methods can be divided into spectroscopy and mass spectrometry technologies. The spectroscopy methods contain laser-induced fluorescence (LIF), UV-absorption spectroscopy, cavity ring-down spectroscopy (CRDS) and matrix isolation and electron spin resonance (MIESR). The mass spectrometry methods contain chemical ionization atmospheric pressure interface time-of-flight mass spectrometry (CI-APi-TOF), chemical ionization mass spectrometry (CIMS), CI-Orbitrap-MS and the third-generation proton transfer reaction-time-of-flight mass spectrometer (PTR3). This article reviews technologies for the speciated detection of RO2 radicals and the applications of these methods. In addition, a comparison of these techniques and the reaction mechanisms of some key species are discussed. Finally, possible gaps are proposed that could be filled by future research into speciated RO2 radicals.
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Affiliation(s)
- Yue Gao
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, State Environmental Protection Key Laboratory of Atmospheric Ozone Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Keding Lu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, State Environmental Protection Key Laboratory of Atmospheric Ozone Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China.
| | - Yuanhang Zhang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, State Environmental Protection Key Laboratory of Atmospheric Ozone Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China.
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11
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Dbouk Z, Belhadj N, Lailliau M, Benoit R, Dagaut P. Characterization of the Autoxidation of Terpenes at Elevated Temperature Using High-Resolution Mass Spectrometry: Formation of Ketohydroperoxides and Highly Oxidized Products from Limonene. J Phys Chem A 2022; 126:9087-9096. [PMID: 36416259 DOI: 10.1021/acs.jpca.2c06323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Low-temperature experiments on the oxidation of limonene-O2-N2 mixtures were conducted in a jet-stirred reactor (JSR) over a range of temperatures (520-800 K) under fuel-lean conditions (equivalence ratio φ = 0.5) with a short residence time (1.5 s) and a pressure of 1 bar. Collected samples of the reaction mixtures were analyzed by (i) online Fourier transform infrared spectroscopy (FTIR) and (ii) Orbitrap Q-Exactive high-resolution mass spectrometry after direct injection or chromatographic separation using reversed-phase ultra-high-performance liquid chromatography (RP-UHPLC) and soft ionization (with positive or negative heated electrospray ionization and atmospheric-pressure chemical ionization). H/D exchange using deuterated water (D2O) and a reaction with 2,4-dinitrophenylhydrazine (2,4-DNPH) were performed to probe the presence of OH, OOH, and C═O groups in the oxidized products. A broad range of oxidation products ranging from water to highly oxygenated products containing five and more O atoms were detected (C7H10O4,5, C8H12O2,4, C8H14O2,4, C9H12O, C9H14O1,3-5, C10H12O2, C10H14O1-9, C10H16O2-5, and C10H18O6). Mass spectrometry analyses were only qualitative, and quantification was performed with FTIR. The results are discussed in terms of reaction routes involving the initial formation of peroxy radicals, H atom transfer, and O2 addition sequences producing a large set of chemical products, including ketohydroperoxides and more oxygenated products. Carbonyl compounds derived from the Waddington oxidation mechanism on exo- and endo-double bonds (C═C) were observed in addition to their products of further oxidation. Products of the Korcek mechanism (carboxylic acids and carbonyls) were also detected.
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Affiliation(s)
- Zahraa Dbouk
- CNRS-INSIS, Institut de Combustion, Aérothermique, Réactivité, Environnement, Avenue de la recherche scientifique, 4507Orléans, France.,Université d'Orléans, Avenue de Parc Floral, 45067Orléans, France
| | - Nesrine Belhadj
- CNRS-INSIS, Institut de Combustion, Aérothermique, Réactivité, Environnement, Avenue de la recherche scientifique, 4507Orléans, France.,Université d'Orléans, Avenue de Parc Floral, 45067Orléans, France
| | - Maxence Lailliau
- CNRS-INSIS, Institut de Combustion, Aérothermique, Réactivité, Environnement, Avenue de la recherche scientifique, 4507Orléans, France.,Université d'Orléans, Avenue de Parc Floral, 45067Orléans, France
| | - Roland Benoit
- CNRS-INSIS, Institut de Combustion, Aérothermique, Réactivité, Environnement, Avenue de la recherche scientifique, 4507Orléans, France
| | - Philippe Dagaut
- CNRS-INSIS, Institut de Combustion, Aérothermique, Réactivité, Environnement, Avenue de la recherche scientifique, 4507Orléans, France
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12
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Wen Z, Yue H, Zhang Y, Lin X, Ma Z, Zhang W, Wang Z, Zhang C, Fittschen C, Tang X. Self-reaction of C2H5O2 and its cross-reaction with HO2 studied with vacuum ultraviolet photoionization mass spectrometry. Chem Phys Lett 2022. [DOI: 10.1016/j.cplett.2022.140034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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13
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Shen H, Vereecken L, Kang S, Pullinen I, Fuchs H, Zhao D, Mentel TF. Unexpected significance of a minor reaction pathway in daytime formation of biogenic highly oxygenated organic compounds. SCIENCE ADVANCES 2022; 8:eabp8702. [PMID: 36269820 PMCID: PMC9586481 DOI: 10.1126/sciadv.abp8702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 09/01/2022] [Indexed: 06/16/2023]
Abstract
Secondary organic aerosol (SOA), formed by oxidation of volatile organic compounds, substantially influence air quality and climate. Highly oxygenated organic molecules (HOMs), particularly those formed from biogenic monoterpenes, contribute a large fraction of SOA. During daytime, hydroxyl radicals initiate monoterpene oxidation, mainly by hydroxyl addition to monoterpene double bonds. Naturally, related HOM formation mechanisms should be induced by that reaction route, too. However, for α-pinene, the most abundant atmospheric monoterpene, we find a previously unidentified competitive pathway under atmospherically relevant conditions: HOM formation is predominately induced via hydrogen abstraction by hydroxyl radicals, a generally minor reaction pathway. We show by observations and theoretical calculations that hydrogen abstraction followed by formation and rearrangement of alkoxy radicals is a prerequisite for fast daytime HOM formation. Our analysis provides an accurate mechanism and yield, demonstrating that minor reaction pathways can become major, here for SOA formation and growth and related impacts on air quality and climate.
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Affiliation(s)
- Hongru Shen
- Department of Atmospheric and Oceanic Sciences & Institute of Atmospheric Sciences, Fudan University, Shanghai 200438, China
| | - Luc Vereecken
- Institute of Energy and Climate Research, IEK-8: Troposphere, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Sungah Kang
- Institute of Energy and Climate Research, IEK-8: Troposphere, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Iida Pullinen
- Institute of Energy and Climate Research, IEK-8: Troposphere, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Hendrik Fuchs
- Institute of Energy and Climate Research, IEK-8: Troposphere, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
- Physikalisches Institut, Universität zu Köln, 50932 Köln, Germany
| | - Defeng Zhao
- Department of Atmospheric and Oceanic Sciences & Institute of Atmospheric Sciences, Fudan University, Shanghai 200438, China
- Shanghai Frontiers Science Center of Atmosphere-Ocean Interaction, Fudan University, Shanghai 200438, China
- Institute of Eco-Chongming (IEC), 20 Cuiniao Rd., Chongming, Shanghai 202162, China
- IRDR ICoE on Risk Interconnectivity and Governance on Weather/Climate Extremes Impact and Public Health, Fudan University, Shanghai 200438, China
| | - Thomas F. Mentel
- Institute of Energy and Climate Research, IEK-8: Troposphere, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
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14
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Pytel K, Marcinkowska R, Rutkowska M, Zabiegała B. Recent advances on SOA formation in indoor air, fate and strategies for SOA characterization in indoor air - A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 843:156948. [PMID: 35753459 DOI: 10.1016/j.scitotenv.2022.156948] [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] [Received: 04/21/2022] [Revised: 06/18/2022] [Accepted: 06/20/2022] [Indexed: 06/15/2023]
Abstract
Recent studies proves that indoor air chemistry differs in many aspects from atmospheric one. People send up to 90 % of their life indoors being exposed to pollutants present in gas, particle and solid phase. Particle phase indoor is composed of particles emitted from various sources, among which there is an indoor source - secondary chemical reactions leading to formation of secondary organic aerosol (SOA). Lately, researchers' attentions turned towards the ultrafine particles, for there are still a lot of gaps in knowledge concerning this field of study, while there is evidence of negative influence of ultrafine particles on human health. Presented review sums up current knowledge about secondary particle formation in indoor environment and development of analytical techniques applied to study those processes. The biggest concern today is studying ROS, for their lifetime in indoor air is very short due to reactions at the very beginning of terpene oxidation process. Another interesting aspect that is recently discovered is monoterpene autooxidation process that leads to HOMs formation that in turn can influence SOA formation yield. A complex studies covering gas phase and particle phase characterization, but also toxicological studies are crucial to fully understand indoor air chemistry leading to ultrafine particle formation.
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Affiliation(s)
- Klaudia Pytel
- Department of Analytical Chemistry, Faculty of Chemistry, Gdańsk University of Technology, 11/12 Narutowicza Str., 80-233 Gdańnsk, Poland
| | - Renata Marcinkowska
- Department of Analytical Chemistry, Faculty of Chemistry, Gdańsk University of Technology, 11/12 Narutowicza Str., 80-233 Gdańnsk, Poland
| | - Małgorzata Rutkowska
- Department of Analytical Chemistry, Faculty of Chemistry, Gdańsk University of Technology, 11/12 Narutowicza Str., 80-233 Gdańnsk, Poland
| | - Bożena Zabiegała
- Department of Analytical Chemistry, Faculty of Chemistry, Gdańsk University of Technology, 11/12 Narutowicza Str., 80-233 Gdańnsk, Poland.
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15
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Synthesis and Characterization of Atmospherically Relevant Hydroxy Hydroperoxides. ATMOSPHERE 2022. [DOI: 10.3390/atmos13040507] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Hydroxy hydroperoxides are formed upon OH oxidation of volatile organic compounds in the atmosphere and may contribute to secondary organic aerosol growth and aqueous phase chemistry after phase transfer to particles. Although the detection methods for oxidized volatile organic compounds improved much over the past decades, the limited availability of synthetic standards for atmospherically relevant hydroxy hydroperoxides prevented comprehensive investigations for the most part. Here, we present a straightforward improved synthetic access to isoprene-derived hydroxy hydroperoxides, i.e., 1,2-ISOPOOH and 4,3-ISOPOOH. Furthermore, we present the first successful synthesis of an α-pinene derived hydroxy hydroperoxide. All products were identified by 1H, 13C NMR spectroscopy for structure elucidation, additional 2D NMR experiments were performed. Furthermore, gas-phase FTIR- and UV/VIS spectra are presented for the first time. Using the measured absorption cross section, the atmospheric photolysis rate of up to 2.1 × 10−3 s−1 was calculated for 1,2-ISOPOOH. Moreover, we present the investigation of synthesized hydroxy hydroperoxides in an aerosol chamber study by online MS techniques, namely PTR-ToFMS and (NO3−)-CI-APi-ToFMS. Fragmentation patterns recorded during these investigations are presented as well. For the (NO3−)-CI-APi-ToFMS, a calibration factor for 1,2-ISOPOOH was calculated as 4.44 × 10−5 ncps·ppbv−1 and a LOD (3σ, 1 min average) = 0.70 ppbv.
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16
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Barber VP, Kroll JH. Chemistry of Functionalized Reactive Organic Intermediates in the Earth's Atmosphere: Impact, Challenges, and Progress. J Phys Chem A 2021; 125:10264-10279. [PMID: 34846877 DOI: 10.1021/acs.jpca.1c08221] [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
The gas-phase oxidation of organic compounds is an important chemical process in the Earth's atmosphere. It governs oxidant levels and controls the production of key secondary pollutants, and hence has major implications for air quality and climate. Organic oxidation is largely controlled by the chemistry of a few reactive intermediates, namely, alkyl (R) radicals, alkoxy (RO) radicals, peroxy (RO2) radicals, and carbonyl oxides (R1R2COO), which may undergo a number of unimolecular and bimolecular reactions. Our understanding of these intermediates, and the reaction pathways available to them, is based largely on studies of unfunctionalized intermediates, formed in the first steps of hydrocarbon oxidation. However, it has become increasingly clear that intermediates with functional groups, which are generally formed later in the oxidation process, can exhibit fundamentally different reactivity than unfunctionalized ones. In this Perspective, we explore the unique chemistry available to functionalized organic intermediates in the Earth's atmosphere. After a brief review of the canonical chemistry available to unfunctionalized intermediates, we discuss how the addition of functional groups can introduce new reactions, either by changing the energetics or kinetics of a given reaction or by opening up new chemical pathways. We then provide examples of atmospheric reaction classes that are available only to functionalized intermediates. Some of these, such as unimolecular H-shift reactions of RO2 radicals, have been elucidated only relatively recently, and can have important impacts on atmospheric chemistry (e.g., on radical cycling or organic aerosol formation); it seems likely that other, as-yet undiscovered reactions of (multi)functional intermediates may also exist. We discuss the challenges associated with the study of the chemistry of such intermediates and review novel experimental and theoretical approaches that have recently provided (or hold promise for providing) new insights into their atmospheric chemistry. The continued use and development of such techniques and the close collaboration between experimentalists and theoreticians are necessary for a complete, detailed understanding of the chemistry of functionalized intermediates and their impact on major atmospheric chemical processes.
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Affiliation(s)
- Victoria P Barber
- Departments of Civil and Environmental Engineering and Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Jesse H Kroll
- Departments of Civil and Environmental Engineering and Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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17
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Rissanen M. Anthropogenic Volatile Organic Compound (AVOC) Autoxidation as a Source of Highly Oxygenated Organic Molecules (HOM). J Phys Chem A 2021; 125:9027-9039. [PMID: 34617440 PMCID: PMC8543447 DOI: 10.1021/acs.jpca.1c06465] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 09/01/2021] [Indexed: 11/30/2022]
Abstract
Gas-phase hydrocarbon autoxidation is a rapid pathway for the production of in situ aerosol precursor compounds. It is a highway to molecular growth and lowering of vapor pressure, and it produces hydrogen-bonding functional groups that allow a molecule to bind into a substrate. It is the crucial process in the formation and growth of atmospheric secondary organic aerosol (SOA). Recently, the rapid gas-phase autoxidation of several volatile organic compounds (VOC) has been shown to yield highly oxygenated organic molecules (HOM). Most of the details on HOM formation have been obtained from biogenic monoterpenes and their surrogates, with cyclic structures and double bonds both found to strongly facilitate HOM formation, especially in ozonolysis reactions. Similar structural features in common aromatic compounds have been observed to facilitate high HOM formation yields, despite the lack of appreciable O3 reaction rates. Similarly, the recently observed autoxidation and subsequent HOM formation in the oxidation of saturated hydrocarbons cannot be initiated by O3 and require different mechanistic steps for initiating and propagating the autoxidation sequence. This Perspective reflects on these recent findings in the context of the direct aerosol precursor formation in urban atmospheres.
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Affiliation(s)
- Matti Rissanen
- Aerosol Physics Laboratory,
Physics Unit, Faculty of Engineering and Natural Sciences, Tampere University, 33720 Tampere, Finland
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