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Fourier transform microwave spectroscopy of CH(2)CFO
Akihiro Watanabe1, Yoshihiro Sumiyoshi, Yasuki Endo
1Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan.
The Journal of Chemical Physics
|June 18, 2009
Summary
The first rotational spectra of the CH(2)CFO radical were observed, revealing its planar structure and dominant formylmethyl resonance. Fluorine substitution minimally impacts the C-C-O pi system.
Area of Science:
- Physical Chemistry
- Molecular Spectroscopy
- Quantum Chemistry
Background:
- The study of reactive intermediates like radicals is crucial for understanding chemical reaction mechanisms.
- The formylmethyl radical (CH(2)CHO) and its derivatives are important in combustion and atmospheric chemistry.
Purpose of the Study:
- To experimentally determine the structure and electronic properties of the CH(2)CFO radical.
- To investigate the electronic structure and bonding in fluorinated formylmethyl-type radicals.
Main Methods:
- Fourier transform microwave (FTMW) spectroscopy was employed to observe rotational transitions.
- Analysis utilized a rigid asymmetric top Hamiltonian suitable for doublet species with nuclear spins.
Main Results:
- Rotational spectra with resolved fine and hyperfine structures were obtained for the first time.
- Seventeen molecular constants, including fine and hyperfine coupling constants, were determined.
- The CH(2)CFO radical was confirmed as planar with a dominant formylmethyl resonance structure (CH(2)CF=O).
Conclusions:
- The formylmethyl-type resonance structure is dominant in the ground electronic state of CH(2)CFO.
- Fluorine substitution has a negligible effect on the C-C-O pi conjugate system.
- The experimental data provides valuable insights into the electronic structure of fluorinated radicals.
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