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Complex and Sustained Quantum Beating Patterns in a Classic IVR System: The 3(1)5(1) Level in S1 p-Difluorobenzene
Jonathan Midgley1, Julia A Davies1, Katharine L Reid1
1School of Chemistry, University of Nottingham, Nottingham, NG7 2RD, United Kingdom.
The Journal of Physical Chemistry Letters
|August 18, 2015
Summary
Picosecond time-resolved photoelectron imaging reveals restricted intramolecular vibrational energy redistribution (IVR) dynamics in p-difluorobenzene. This study identified six distinct IVR periods, highlighting the molecule's high symmetry and rigid structure.
Area of Science:
- Chemical Physics
- Molecular Dynamics
- Spectroscopy
Background:
- Intramolecular vibrational energy redistribution (IVR) is crucial for understanding energy flow in molecules.
- Previous studies on p-difluorobenzene lacked the time and energy resolution to fully characterize IVR dynamics.
Purpose of the Study:
- To investigate the IVR dynamics in p-difluorobenzene following excitation of the 3(1)5(1) level.
- To resolve individual vibrational state behavior and identify distinct beating periods.
Main Methods:
- Utilized picosecond time-resolved photoelectron imaging.
- Achieved superior time resolution while maintaining sufficient energy resolution.
Main Results:
- Identified six distinct beating periods in photoelectron intensity, with only one previously observed.
- Demonstrated that IVR dynamics are confined to a limited number of vibrational levels despite high excitation energy.
Conclusions:
- The restricted IVR in p-difluorobenzene is attributed to its high symmetry and rigid molecular structure.
- The findings provide new insights into energy dissipation pathways in highly symmetric molecules.
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