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Published on: July 27, 2022
Ionization-induced π → H site-switching in phenol-CH4 complexes studied using IR dip spectroscopy
Mitsuhiko Miyazaki1, Akihiro Takeda, Matthias Schmies
1Chemical Resources Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Yokohama, 226-8503, Japan. mfujii@res.titech.ac.jp.
Photoionization of phenol-methane complexes reveals a shift from pi-bound to hydrogen-bonded structures. This ionization-induced structural change occurs with high efficiency in methane complexes due to vibrational energy redistribution.
Area of Science:
- Physical Chemistry
- Spectroscopy
- Molecular Interactions
Background:
- Phenol-CH4 complexes exhibit unique structures in their electronic ground states.
- Understanding structural dynamics upon ionization is crucial for molecular science.
Purpose of the Study:
- To investigate the structural changes in phenol-CH4 complexes following photoionization.
- To compare the behavior of CH4 with other ligands like Ar and Kr.
Main Methods:
- Infrared (IR) spectroscopy was employed to study phenol-CH4 complexes.
- Complexes were generated in a supersonic expansion and analyzed before and after photoionization.
Main Results:
- The neutral phenol-CH4 complex adopts a pi-bound geometry.
- Upon ionization, the complex transforms into a hydrogen-bonded structure with a red-shifted OH stretching vibration.
- This ionization-induced pi to H migration occurs with unity yield for CH4, unlike other studied ligands.
Conclusions:
- The observed structural transformation is driven by photoionization.
- Intracluster vibrational energy redistribution processes are key to the high yield of migration in phenol-CH4 complexes.
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