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Published on: May 29, 2018
Photoionization-induced large-amplitude pendular motion in phenol(+)-Kr
Mitsuhiko Miyazaki1, Akihiro Takeda, Shun-ichi Ishiuchi
1Chemical Resources Laboratory, Tokyo Institute of Technology, Yokohama 226-8503, Japan.
Photoionization of phenol-krypton complexes reveals site switching dynamics. The krypton atom moves between aromatic ring sites, mimicking pendular motion.
Area of Science:
- Physical Chemistry
- Molecular Spectroscopy
- Chemical Physics
Background:
- Phenol-Kr complexes exhibit distinct π- and H-structures.
- Photoionization can induce structural rearrangements in molecular complexes.
- Understanding intermolecular dynamics is crucial for reaction mechanisms.
Purpose of the Study:
- To investigate the intermolecular motion of phenol(+)-Kr cation.
- To probe ionization-induced structural changes using time-resolved spectroscopy.
- To elucidate the delocalization pathway of the Kr atom.
Main Methods:
- Picosecond time-resolved infrared spectroscopy.
- Photoionization of neutral phenol-Kr π-structure.
- Analysis of OH stretch band evolution over time.
Main Results:
- Initial spectrum shows free OH stretch of the π-structure.
- Appearance of hydrogen-bonded OH stretch indicates π → H site switching after picoseconds.
- Long-delay spectra reveal Kr atom delocalization via OH-site, resembling pendular motion.
Conclusions:
- Ionization triggers site switching in phenol-Kr complexes.
- Kr atom exhibits pendular motion between π-sites through the OH-site.
- Picosecond spectroscopy effectively captures ultrafast molecular dynamics.
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