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Updated: Nov 4, 2025

Versatile CO2 Transformations into Complex Products: A One-pot Two-step Strategy
Published on: November 9, 2019
Reactivity and internal dynamics in the Criegee intermediate CH2OOCO2 system: A rotational study
Carlos Cabezas1, Adam M Daly2, Yasuki Endo3
1Instituto de Física Fundamental (IFF-CSIC), Group of Molecular Astrophysics, C/Serrano 121, 28006 Madrid, Spain.
Abstract:
The reaction system between the simplest Criegee intermediate, CH2OO, and the greenhouse gas CO2 has been investigated by Fourier transform microwave spectroscopy. The CH2OO-CO2 weakly bound complex was identified in the rotational spectrum, where inversion doublets due to the tunnelling motion between two equivalent configurations of the complex, with CO2 located at one side or the other side of the CH2OO plane, were observed. Using a two-state torsion-rotation Hamiltonian, a complete set of rotational and centrifugal distortion constants for both tunneling states were derived. In addition, the torsional energy difference between both states could be accurately determined, being 23.9687 MHz. The non-observation of the cycloaddition reaction product is in agreement with our ab initio calculations and with previous results that concluded that the reactivity of CIs toward CO2 is measured to be quite limited.
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