Premium
Isomerization and Decomposition of a Criegee Intermediate in the Ozonolysis of Alkenes: Dynamics Using a Multireference Potential
Author(s) -
Kalinowski Jaroslaw,
Räsänen Markku,
Hein Petri,
Kilpeläinen Ilkka,
Gerber R. Benny
Publication year - 2014
Publication title -
angewandte chemie
Language(s) - English
Resource type - Journals
eISSN - 1521-3757
pISSN - 0044-8249
DOI - 10.1002/ange.201307286
Subject(s) - chemistry , isomerization , computational chemistry , ab initio , transition state , multireference configuration interaction , decomposition , ozonolysis , wave function , formic acid , photochemistry , atomic physics , density functional theory , organic chemistry , basis set , physics , catalysis
The isomerization and decomposition dynamics of the simplest Criegee intermediate CH 2 OO have been studied by classical trajectory simulations using the multireference ab initio MR‐PT2 potential on the fly. A new, accelerated algorithm for dynamics with MR‐PT2 was used. For an initial temperature of 300 K, starting from the transition state from CH 2 OO→CH 2 O 2 , the system reaches the dioxirane structure in around 50 fs, then isomerizes to formic acid (in ca. 2800 fs), and decomposes into CO+H 2 O at around 2900 fs. The contributions of different configurations to the multiconfigurational total electronic wave function vary dramatically along the trajectory, with diradical contributions being important for transition states corresponding to H‐atom transfers, while being only moderately significant for CH 2 OO. The implications for reactions of Criegee intermediates are discussed.