Ahn Furudate Michiko, Hagebaum-Reignier Denis, Jeung Gwang-Hi
Department of Mechatronics Engineering, Chungnam National University, 99 Daehak-ro Yuseong-gu, Daejeon 34134, South Korea.
Aix Marseille Univ, CNRS, Centrale Med ISM2, Marseille, 00000 France.
J Phys Chem A. 2025 May 8;129(18):4002-4014. doi: 10.1021/acs.jpca.4c08109. Epub 2025 Apr 29.
The singlet and triplet electronic states of the CO complex are studied with the best available variational quantum chemical methods, CASSCF and MRCI, using a flexible basis set without imposing any symmetry restriction. A large domain of the potential energy surfaces correlated with the lowest four reactant states of CO + O is explored. Several pathways leading to two different types of isomers (star-shaped and chain-shaped) are found for both singlet and triplet spin states, and their spectroscopic properties are characterized. Among these pathways, three reaction pathways on high-lying singlet potential energy surfaces leading to the CO + O dissociation channel are reported for the first time, as well as four intersystem crossing points between the triplet and singlet surfaces. Change in electronic properties along different reaction paths is analyzed in detail.
