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Updated: Jan 15, 2026

Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
Ab initio study of the simplest Criegee intermediate CH2OO: equilibrium structure, spectroscopic properties and
Lihan Chi1, Yanli Liu2, Meishan Wang3
1Department of Applied Physics, School of Physics, Nanjing University of Science and Technology, 210094, Nanjing, Jiangsu, People's Republic of China.
Context:
The simplest Criegee intermediate, play a critical role in the oxidizing capacity of the Earth's troposphere. While substantial research has advanced our understanding of CH2OO over the past decade, comprehensive investigations into the structure, spectroscopic properties and anharmonic force fields remain notably underexplored. Here, we report the equilibrium structures, ground-state rotational constants, fundamental frequencies, quartic and sextic centrifugal distortion constants of CH2OO. The results indicate that the CAM-B3LYP is more suitable for this study than that of B3LYP and ωB97XD functionals. We hope that our work will serve as a reference for relevant studies on CH2OO and other Criegee intermediates.
Methods:
The calculations of structure optimization, spectroscopic properties, and anharmonic force fields of CH2OO are performed by B3LYP, CAM-B3LYP, and ωB97XD functionals in combination with 6-311 + + G** and aug-cc-pVQZ basis sets, respectively, by the Gaussian16 program suite.
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