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Title: Theoretical analysis of the OH-initiated atmospheric oxidation reactions of imidazole

Journal Article · · Physical Chemistry Chemical Physics
DOI: https://doi.org/10.1039/d4cp02103g · OSTI ID:2427000

Imidazoles are present in Earth's atmosphere in both the gas-phase and in aerosol particles, and have been implicated in the formation of brown carbon aerosols. The gas-phase oxidation of imidazole (C3N2H4) by hydroxyl radicals has been shown to be preferentially initiated via OH-addition to position C5, producing the 5-hydroxyimidazolyl radical adduct. However, the fate of this adduct upon reaction with O2 in the atmospheric gas-phase is currently unknown. We employed an automated approach to investigate the reaction mechanism and kinetics of imidazole's OH-initiated gas-phase oxidation, in the presence of O2 and NOx. The explored mechanism included reactions available to first-generation RO2 radicals, as well as alkoxyl radicals produced from RO2 + NO reactions. Product distributions were obtained by assembling and solving a master equation, under conditions relevant to the Earth's atmosphere. Our calculations show a complex, branched reaction mechanism, which nevertheless converges to yield two major closed-shell products: 4H-imidazol-4-ol (4H-4ol) and N,N′-diformylformamidine (FMF). At 298 K and 1 atm, we estimate the yields of 4H-4ol and FMF from imidazole oxidation initiated via OH-addition to position C5 to be 34 : 66, 12 : 85 and 2 : 95 under 10 ppt, 100 ppt and 1 ppb of NO respectively. This work also revealed O2-migration pathways between the α-N-imino peroxyl radical isomers. This reaction channel is fast for the first-generation RO2 radicals, and may be important during the atmospheric oxidation of other unsaturated organic nitrogen compounds as well.

Research Organization:
Sandia National Laboratories (SNL-CA), Livermore, CA (United States)
Sponsoring Organization:
Research Council of Finland; USDOE; USDOE Laboratory Directed Research and Development (LDRD) Program; USDOE National Nuclear Security Administration (NNSA); USDOE Office of Science (SC), Basic Energy Sciences (BES). Chemical Sciences, Geosciences & Biosciences Division (CSGB)
Grant/Contract Number:
NA0003525
OSTI ID:
2427000
Report Number(s):
SAND--2025-12919J
Journal Information:
Physical Chemistry Chemical Physics, Journal Name: Physical Chemistry Chemical Physics Journal Issue: 36 Vol. 26; ISSN 1463-9076; ISSN 1463-9084
Publisher:
Royal Society of Chemistry (RSC)Copyright Statement
Country of Publication:
United States
Language:
English

References (98)

MMFF VII. Characterization of MMFF94, MMFF94s, and other widely available force fields for conformational energies and for intermolecular-interaction energies and geometries journal May 1999
Unimolecular Reactions of Peroxy Radicals in Atmospheric Chemistry and Combustion journal September 2010
Efficient diffuse function-augmented basis sets for anion calculations. III. The 3-21+G basis set for first-row elements, Li-F journal October 1983
Ueber die Einwirkung des Ammoniaks auf Glyoxal journal January 1858
Separation and quantification of imidazoles in atmospheric particles using LC–Orbitrap‐MS journal November 2019
The influence of polarization functions on molecular orbital hydrogenation energies journal January 1973
Rate studies of the reactions of the (CH3)2N radical with O2, NO, and NO2 journal November 1979
The testing of models for unimolecular decomposition via inverse laplace transformation of experimental recombination rate data journal May 1986
Atmospheric amines – Part I. A review journal January 2011
A systematic theoretical study of imines formation from the atmospheric reactions of RnNH2−n with O2 and NO2 (R = CH3 and CH3CH2; n = 1 and 2) journal August 2012
Temperature- and pH-dependent aqueous-phase kinetics of the reactions of glyoxal and methylglyoxal with atmospheric amines and ammonium sulfate journal October 2013
Aliphatic amines at the Cape Verde Atmospheric Observatory: Abundance, origins and sea-air fluxes journal April 2019
Mechanism and predictive model development of reaction rate constants for N-center radicals with O2 journal December 2019
Ab initio kinetic mechanism of OH-initiated atmospheric oxidation of pyrrole journal January 2021
Reaction Mechanism Generator: Automatic construction of chemical kinetic mechanisms journal June 2016
KinBot: Automated stationary point search on potential energy surfaces journal March 2020
Computational study of the stability of α-hydroperoxyl- or α-alkylperoxyl substituted alkyl radicals journal August 2004
W4-11: A high-confidence benchmark dataset for computational thermochemistry derived from first-principles W4 data journal July 2011
Kinetics of elementary reactions in low-temperature autoignition chemistry journal August 2011
An experimental and computational investigation of the reaction between pent-1-en-3-yl radicals and oxygen molecules under autoignition conditions journal January 2023
Insights into high concentrations of particle-bound imidazoles in the background atmosphere of southern China: Potential sources and influencing factors journal February 2022
Aerial drone furnished with miniaturized versatile air sampling systems for selective collection of nitrogen containing compounds in boreal forest journal February 2022
Long-term stable and efficient degradation of ornidazole with minimized by-product formation by a biological sulfidogenic process based on elemental sulfur journal February 2024
Human health risk assessment of nitrosamines and nitramines for potential application in CO2 capture journal July 2014
Highly Oxygenated Organic Molecules (HOM) from Gas-Phase Autoxidation Involving Peroxy Radicals: A Key Contributor to Atmospheric Aerosol journal January 2019
New Insights into the Radical Chemistry and Product Distribution in the OH-Initiated Oxidation of Benzene journal October 2020
First Quantification of Imidazoles in Ambient Aerosol Particles: Potential Photosensitizers, Brown Carbon Constituents, and Hazardous Components journal January 2016
Gas-Phase Mechanisms of the Reactions of Reduced Organic Nitrogen Compounds with OH Radicals journal October 2016
Evidence for the Formation of Imidazole from Carbonyls and Reduced Nitrogen Species at the Individual Particle Level in the Ambient Atmosphere journal October 2020
Interfacial Ozone Oxidation Chemistry at a Riverine Surface Microlayer as a Source of Nitrogen Organic Compounds journal May 2022
Automated Reaction Kinetics of Gas-Phase Organic Species over Multiwell Potential Energy Surfaces journal January 2023
Experimental and Theoretical Study of the OH-Initiated Degradation of Piperidine under Simulated Atmospheric Conditions journal March 2024
Unimolecular HO 2 Loss from Peroxy Radicals Formed in Autoxidation Is Unlikely under Atmospheric Conditions journal May 2016
Importance of Unimolecular HO 2 Elimination in the Heterogeneous OH Reaction of Highly Oxygenated Tartaric Acid Aerosol journal July 2016
Photoactivated Production of Secondary Organic Species from Isoprene in Aqueous Systems journal November 2016
Cost-Effective Implementation of Multiconformer Transition State Theory for Peroxy Radical Hydrogen Shift Reactions journal December 2016
OH-Initiated Oxidation of Imidazoles in Tropospheric Aqueous-Phase Chemistry journal January 2019
Effects of Organic Matrices on Nucleophilic Aqueous Aerosol Chemistry: Yields and Mechanistic Insight for Brown Carbon Formation from Glyoxal and Ammonia journal June 2022
Atmospheric Oxidation of Imine Derivative of Piperazine Initiated by OH Radical journal September 2022
Atmospheric Oxidation of Piperazine Initiated by OH: A Theoretical Kinetics Investigation journal September 2019
The Atmospheric Chemistry of Alkoxy Radicals journal December 2003
Optical Properties of Secondary Organic Aerosols and Their Changes by Chemical Processes journal February 2015
Chemistry of Atmospheric Brown Carbon journal February 2015
Molecular Characterization of Nitrogen-Containing Organic Compounds in Biomass Burning Aerosols Using High-Resolution Mass Spectrometry journal May 2009
Secondary Organic Aerosol-Forming Reactions of Glyoxal with Amino Acids journal April 2009
Molecular Parameters for Normal Fluids. Lennard-Jones 12-6 Potential journal August 1966
Fitting of pressure-dependent kinetic rate data by master equation/inverse Laplace transform analysis journal September 1995
Gas-Phase Reactions of (CH3)2N Radicals with NO and NO2 journal February 1994
Polarographic and optical pulse radiolysis study of the radicals formed by hydroxyl radical attack on imidazole and related compounds in aqueous solutions journal August 1975
Electron spin resonance study of the reaction of hydroxyl radicals with pyrrole, imidazole, and related compounds journal June 1973
Tunnelling Corrections for Unsymmetrical Eckart Potential Energy Barriers journal March 1962
Thermodynamics and Kinetics of Imidazole Formation from Glyoxal, Methylamine, and Formaldehyde: A Computational Study journal March 2011
Comprehensive NO-Dependent Study of the Products of the Oxidation of Atmospherically Relevant Aromatic Compounds journal May 2011
MESMER: An Open-Source Master Equation Solver for Multi-Energy Well Reactions journal September 2012
CH 2 NH 2 + O 2 and CH 3 CHNH 2 + O 2 Reaction Kinetics: Photoionization Mass Spectrometry Experiments and Master Equation Calculations journal March 2014
Atmospheric Oxidation Mechanism of Toluene journal June 2014
Experimental and Theoretical Understanding of the Gas Phase Oxidation of Atmospheric Amides with OH Radicals: Kinetics, Products, and Mechanisms journal July 2014
Atmospheric Gas Phase Chemistry of CH 2 ═NH and HNC. A First-Principles Approach journal July 2014
Electronic Structure of a Transient Histidine Radical in Liquid Aqueous Solution:  EPR Continuous-Flow Studies and Density Functional Calculations journal February 1999
Mechanism of Hydroxyl Radical Addition to Imidazole and Subsequent Water Elimination journal June 1999
Concerted HO2 Elimination from α-Aminoalkylperoxyl Free Radicals: Experimental and Theoretical Evidence from the Gas-Phase NH2CHCO2 + O2 Reaction journal March 2012
Autoxidation of Organic Compounds in the Atmosphere journal September 2013
endo-Cyclization of unsaturated RO 2 radicals from the gas-phase ozonolysis of cyclohexadienes journal January 2017
Theoretical analysis of glyoxal condensation with ammonia in aqueous solution journal January 2019
Atmospheric oxidation reactions of imidazole initiated by hydroxyl radicals: kinetics and mechanism of reactions and atmospheric implications journal January 2019
Comment on “Atmospheric oxidation reactions of imidazole initiated by hydroxyl radicals: kinetics and mechanism of reactions and atmospheric implications” by Safaei et al., Phys. Chem. Chem. Phys., 2019, 21, 8445 journal January 2019
Atmospheric chemistry of oxazole: the mechanism and kinetic studies of the oxidation reaction initiated by OH radicals journal January 2021
Photosensitization mechanisms at the air–water interface of aqueous aerosols journal January 2022
Long-range corrected hybrid density functionals with damped atom–atom dispersion corrections journal January 2008
Laboratory studies of organic peroxy radical chemistry: an overview with emphasis on recent issues of atmospheric significance journal January 2012
Organic aerosol formation photo-enhanced by the formation of secondary photosensitizers in aerosols journal January 2013
Self‐Consistent Molecular‐Orbital Methods. IX. An Extended Gaussian‐Type Basis for Molecular‐Orbital Studies of Organic Molecules journal January 1971
Self—Consistent Molecular Orbital Methods. XII. Further Extensions of Gaussian—Type Basis Sets for Use in Molecular Orbital Studies of Organic Molecules journal March 1972
The Activated Complex in Chemical Reactions journal February 1935
Two-electron distribution functions and short-range electron correlations of atoms and molecules by first principles T-matrix calculations journal September 2006
Systematically convergent basis sets for explicitly correlated wavefunctions: The atoms H, He, B–Ne, and Al–Ar journal February 2008
Simplified CCSD(T)-F12 methods: Theory and benchmarks journal February 2009
Gaussian basis sets for use in correlated molecular calculations. I. The atoms boron through neon and hydrogen journal January 1989
Electron affinities of the first‐row atoms revisited. Systematic basis sets and wave functions journal May 1992
A new mixing of Hartree–Fock and local density‐functional theories journal January 1993
The Molpro quantum chemistry package journal April 2020
Dataset of noncovalent intermolecular interaction energy curves for 24 small high-spin open-shell dimers journal April 2021
Examining the ground and first excited states of methyl peroxy radical with high-level coupled-cluster theory journal July 2015
Estimation of Pure-Component Properties from Group-Contributions journal July 1987
Is either direct photolysis or photocatalysed H-shift of peroxyl radicals a competitive pathway in the troposphere? journal September 2020
The Penetration of a Potential Barrier by Electrons journal June 1930
Development of the Colle-Salvetti correlation-energy formula into a functional of the electron density journal January 1988
Direct observation and kinetics of a hydroperoxyalkyl radical (QOOH) journal February 2015
COMPOSIÇÃO QUÍMICA E ATIVIDADES FOTOPROTETORA E ANTIRADICALAR IN VITRO DOS GALHOS DE Platonia insignis (CLUSIACEAE) journal January 2021
Aerosol mass spectrometer constraint on the global secondary organic aerosol budget journal January 2011
Estimation of rate coefficients and branching ratios for gas-phase reactions of OH with aliphatic organic compounds for use in automated mechanism construction journal January 2018
Estimation of rate coefficients and branching ratios for gas-phase reactions of OH with aromatic organic compounds for use in automated mechanism construction journal January 2018
Estimation of rate coefficients and branching ratios for reactions of organic peroxy radicals for use in automated mechanism construction journal January 2019
Modeling radiative and climatic effects of brown carbon aerosols with the ARPEGE-Climat global climate model journal September 2022
Vertical profiles of volatile organic compounds and fine particles in atmospheric air by using an aerial drone with miniaturized samplers and portable devices journal May 2023
Glyoxal uptake on ammonium sulphate seed aerosol: reaction products and reversibility of uptake under dark and irradiated conditions journal January 2009
The formation, properties and impact of secondary organic aerosol: current and emerging issues journal January 2009
Quantification of Imidazole Compounds in Ambient Aerosols at Suburban and Forest Sites in Western Japan journal December 2019