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Updated: Apr 5, 2026

Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
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.
Abstract:
Using picosecond time-resolved photoelectron imaging, we have studied the intramolecular vibrational energy redistribution (IVR) dynamics that occur following the excitation of the 3(1)5(1) level, which lies 2068 cm(-1) above the S1 origin in p-difluorobenzene. Our technique, which has superior time resolution to that of earlier studies but retains sufficient energy resolution to identify the behavior of individual vibrational states, enables us to determine six distinct beating periods in photoelectron intensity, only one of which has been observed previously. Analysis shows that the IVR dynamics are restricted among only a handful of vibrational levels, despite the relatively high excitation energy. This is deduced to be a consequence of the high symmetry and rigid structure of p-difluorobenzene.
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