Infrared-driven unimolecular reaction of CH3CHOO Criegee intermediates to OH radical products

Science ◽  
2014 ◽  
Vol 345 (6204) ◽  
pp. 1596-1598 ◽  
Author(s):  
F. Liu ◽  
J. M. Beames ◽  
A. S. Petit ◽  
A. B. McCoy ◽  
M. I. Lester
Keyword(s):  
Unimolecular Reaction ◽  
Oh Radical ◽  
Criegee Intermediates

scholarly journals Deep tunneling in the unimolecular decay of CH3CHOO Criegee intermediates to OH radical products

2016 ◽  
Vol 145 (23) ◽  
pp. 234308 ◽  
Author(s):  
Yi Fang ◽  
Fang Liu ◽  
Victoria P. Barber ◽  
Stephen J. Klippenstein ◽  
Anne B. McCoy ◽  
...  
Keyword(s):  
Oh Radical ◽  
Criegee Intermediates

scholarly journals Tunneling effects in the unimolecular decay of (CH3)2COO Criegee intermediates to OH radical products

2017 ◽  
Vol 146 (13) ◽  
pp. 134307 ◽  
Author(s):  
Yi Fang ◽  
Victoria P. Barber ◽  
Stephen J. Klippenstein ◽  
Anne B. McCoy ◽  
Marsha I. Lester
Keyword(s):  
Oh Radical ◽  
Criegee Intermediates

scholarly journals Direct observation of unimolecular decay of CH3CH2CHOO Criegee intermediates to OH radical products

2016 ◽  
Vol 145 (4) ◽  
pp. 044312 ◽  
Author(s):  
Yi Fang ◽  
Fang Liu ◽  
Stephen J. Klippenstein ◽  
Marsha I. Lester
Keyword(s):  
Direct Observation ◽  
Oh Radical ◽  
Criegee Intermediates

scholarly journals Communication: Real time observation of unimolecular decay of Criegee intermediates to OH radical products

2016 ◽  
Vol 144 (6) ◽  
pp. 061102 ◽  
Author(s):  
Yi Fang ◽  
Fang Liu ◽  
Victoria P. Barber ◽  
Stephen J. Klippenstein ◽  
Anne B. McCoy ◽  
...  
Keyword(s):  
Real Time ◽  
Oh Radical ◽  
Criegee Intermediates ◽  
Time Observation ◽  
Real Time Observation

scholarly journals Unimolecular dissociation dynamics of vibrationally activated CH3CHOO Criegee intermediates to OH radical products

2016 ◽  
Vol 8 (5) ◽  
pp. 509-514 ◽  
Author(s):  
Nathanael M. Kidwell ◽  
Hongwei Li ◽  
Xiaohong Wang ◽  
Joel M. Bowman ◽  
Marsha I. Lester
Keyword(s):  
Unimolecular Dissociation ◽  
Oh Radical ◽  
Criegee Intermediates ◽  
Dissociation Dynamics

scholarly journals Velocity map imaging of OH radical products from IR activated (CH3)2COO Criegee intermediates

2016 ◽  
Vol 145 (10) ◽  
pp. 104307 ◽  
Author(s):  
Hongwei Li ◽  
Nathanael M. Kidwell ◽  
Xiaohong Wang ◽  
Joel M. Bowman ◽  
Marsha I. Lester
Keyword(s):  
Velocity Map Imaging ◽  
Oh Radical ◽  
Criegee Intermediates

scholarly journals Understanding the oxidants transition and SOA property in limonene ozonolysis: Role of different double bonds, radical chemistry, and water

2018 ◽  
Author(s):  
Yiwei Gong ◽  
Zhongming Chen ◽  
Huan Li
Keyword(s):  
Radical Scavenger ◽  
Oh Radical ◽  
Aerosol Formation ◽  
Double Bonds ◽  
Radical Chemistry ◽  
Criegee Intermediates ◽  
Partitioning Coefficients ◽  
Reaction With Water ◽  
Relationship Of ◽  
Partitioning Behavior

Abstract. Volatile organic compounds (VOCs) play an important role in air quality and climate change, largely because of their contribution to atmospheric oxidation capacity and secondary organic aerosol (SOA) formation through their oxidation. In this study, a series of products including peroxides and carbonyl compounds in both gaseous and particulate phases were simultaneously detected to help us investigate the oxidants transition and SOA property in limonene ozonolysis. Reactants ratio, OH radical scavenger and relative humidity (RH) were controlled to discuss the effect of endocyclic and exocyclic double bonds (DBs), radial chemistry and water. Alkene ozonolysis not only consumed but also regenerated oxidants, which made a great impact on atmospheric chemical processes. For this issue, we first paid attention to the generation of stabilized Criegee intermediates (SCIs) and OH radical. The variation of H2O2 and hydroxymethyl hydroperoxide (HMHP) formation with RH showed the importance of the reaction with water for limonene SCIs, and the estimated SCIs yields of endocyclic and exocyclic DBs were ~ 0.24 and ~ 0.43, respectively. OH yield was determined by adding sufficient OH scavenger, and the OH yields of endocyclic and exocyclic DBs were ~ 0.65 and ~ 0.24, respectively. The results indicated that in limonene ozonolysis the endocyclic DB was inclined to generate OH radical through hydroperoxide channel, while the exocyclic DB had higher fraction of forming SCIs. Besides, other gas-phase and particle-phase peroxides were also studied. The formation of peroxyformic acid (PFA) and peroxyacetic acid (PAA) were promoted significantly by the increasing RH and the oxidation degree, and the discrepancy between the experimental and model results suggested some missing formation pathways. Considerable H2O2 generation from SOA in aqueous phase was observed especially at high [O3]/[limonene], which was mainly attributed to the hydration and decomposition of particulate unstable peroxides such as peroxycarboxylic acids and peroxyhemiacetals. Different DBs and radical chemistry revealed their influence on aerosol property through affecting the behavior of SOA on generating H2O2. As a species owning high SOA formation potential, another key issue we investigated in limonene ozonolysis was SOA property, for which peroxides and carbonyls were chosen as representatives. The results showed that in limonene SOA, peroxides could account for 0.07–0.19 at low [O3]/[limonene] and 0.40–0.58 at high [O3]/[limonene], which confirmed the important contribution of peroxides to aerosol formation. The partitioning behavior of peroxides showed that multigeneration oxidation helped produce more low-volatility peroxides, which provided some explanation for higher SOA yield. The partitioning behavior of carbonyls was also discussed and the experimental partitioning coefficients (Kp) were usually several orders of magnitude higher than theoretical values, yet the relationship of Kp observed in laboratory with vapor pressure offered some reference for predicting the contribution of carbonyls to SOA formation. This study provided new insights into the oxidants transition and SOA property in limonene ozonolysis, and limonene showed its specificity in many aspects when both endocyclic and exocyclic DBs were ozonated. We suggested that the atmospheric implications of terpenes containing more than one DB and the properties of particulate products especially peroxides still needed further study.

How does substitution affect the unimolecular reaction rates of Criegee intermediates?

2017 ◽  
Vol 19 (19) ◽  
pp. 12075-12084 ◽  
Author(s):  
Cangtao Yin ◽  
Kaito Takahashi
Keyword(s):  
Substitution Effect ◽  
Reaction Rates ◽  
Unimolecular Reaction ◽  
Criegee Intermediates

Unimolecular reaction rates of Criegee intermediates show substitution effect.

Sign in / Sign up

Export Citation Format

Share Document