Theoretical Study on the Reaction Mechanism and Kinetics of Criegee Intermediate CH₂OO with Acrolein

Abstract

The detailed reaction mechanism and kinetics of Criegee intermediate CH 2 OO with acrolein were investigated. CH 2 OO may add to the CO or CC double bond of acrolein to form a five-membered ring adducts, and it may also insert the terminal oxygen atom or insert itself into the C−H bond of acrolein. The addition reactions are more favorable in energy than the insertion reactions. The master equation calculation show that the most competitive reaction channel is the 1,3-cycloaddition of CH 2 OO across the CO double bond forming the secondary ozonide (SOZ). The lowest energy pathway for SOZ decomposition involves the formation of the singlet biradical intermediate by ring fission, the H-shift isomerization and the dissociation to products. The calculated overall rate constant decreases as the temperature increases from 200 to 500 K, and at 298 K, it is 4.31 × 10 −12 cm 3 molecule −1 s −1 . The branching ratio of collisionally stabilized SOZ increases with the increase of pressure. At low pressure, some of SOZ decompose to HCOOH + acrolein or HCHO + acrylic acid. The pressure dependence of this reaction is in agreement with the previous theoretical and experimental observations for the reaction of CH 2 OO with acetaldehyde.

Atmospheric Chemistry of Enols: The Formation Mechanisms of Formic and Peroxyformic Acids in Ozonolysis of Vinyl Alcohol

“…The restricted formalism (RM06-2X) was used for the closed-shell species, whereas the “broken symmetry DFT” methodology was used for ozone. Ozone has a multireference wave function, which cannot be described using the single-reference methodologies, but its singlet biradical character can be partially accommodated using the “broken symmetry DFT” methodology which uncouples α and β radicals in the singlet wave function. , All transition state (TS) structures were confirmed by single imaginary vibrational frequency. For key pathways, the TSs were further confirmed by using the intrinsic reaction coordinate (IRC) calculations to obtain their minimum energy paths.…”

Theoretical Study on Criegee Intermediate’s Role in Ozonolysis of Acrylic Acid

“…It is reported recently that CH 2 OO, when it reacts with acrolein, a similar species in structure, can also perform cycloadditions and insertions. And besides those, CH 2 OO and acrolein can have another insertion, leading to formaldehyde and acrylic acid, which was not found in our inquiry. Potential energy surface (PES) of acrylic acid and CH 2 OO was investigated using ab initio quantum chemistry method.…”

Reaction between Criegee Intermediate CH2OO and Isobutyraldehyde: Kinetics and Atmospheric Implications

“…References CH 2 OO + HCHO 5.89×10 À 11 HP limit, [a] 300 K Theoretical -4.47 Long et al [51] 5.13×10 À 11 760 Torr, 298 K Theoretical Zhang et al [52] CH 2 OO + CH 3 CHO (9.5 � 0.7)×10 À 13 4 Torr, 293 K PIMS [c] Taatjes et al [18] 1.7×10 À 12 HP limit, 298 K HCHO LIF [d] Stone et al [8] (1.7 � 0.5)×10 À 12 760 Torr, 297 K CI-Api-TOF-MS [e] Berndt et al [19] (1.2 � 0.2)×10 À 12 25 Torr, 298 K UV abs. [f] À 2.2 � 0.6 Elsamra et al [50] 2.3×10 À 12 LP limit [b] , 298 K Theoretical À 2.1 Elsamra et al [50] CH 2 OO + C 2 H 5 CHO (3.23 � 0.49)×10 À 12 50 Torr, 298 K OH LIF [g] À 1.99 � 0.23 Liu et al [20] 2.44×10 À 12 298 K Theoretical Kaipara et al [67] CH [72] 4.31×10 À 12 298 K Theoretical Sun et al [73] CH 2 OO + MVK (5.0 � 0.4)×10 À 13 4 Torr, 300 K PIMS Eskola et al [74] CH 2 OO + MACR (4.4 � 1.0)×10 À 13 4 Torr, 300 K PIMS Eskola et al [74] 1.00×10 À 12 300 K Theoretical Cai et al [17] CH 2 OO + (CH 3 ) 2 CO…”