The OH+cation is a well‐known diatomic for which the triplet (3Σ−) ground state is 50.5 kcal mol−1more stable than its corresponding singlet (1Δ) excited state. However, the singlet forms a strong donor–acceptor bond to argon with a bond energy of 66.4 kcal mol−1at the CCSDT(Q)/CBS level, making the singlet ArOH+cation 3.9 kcal mol−1more stable than the lowest energy triplet complex. Both singlet and triplet isomers of this molecular ion were prepared in a cold molecular beam using different ion sources. Infrared photodissociation spectroscopy in combination with messenger atom tagging shows that the two spin isomers exhibit completely different spectral signatures. The ground state of ArOH+is the predicted singlet with a covalent Ar−O bond.
The OH+cation is a well‐known diatomic for which the triplet (3Σ−) ground state is 50.5 kcal mol−1more stable than its corresponding singlet (1Δ) excited state. However, the singlet forms a strong donor–acceptor bond to argon with a bond energy of 66.4 kcal mol−1at the CCSDT(Q)/CBS level, making the singlet ArOH+cation 3.9 kcal mol−1more stable than the lowest energy triplet complex. Both singlet and triplet isomers of this molecular ion were prepared in a cold molecular beam using different ion sources. Infrared photodissociation spectroscopy in combination with messenger atom tagging shows that the two spin isomers exhibit completely different spectral signatures. The ground state of ArOH+is the predicted singlet with a covalent Ar−O bond.
more » « less- NSF-PAR ID:
- 10055189
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 57
- Issue:
- 18
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 5081-5085
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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