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Updated: Aug 7, 2026

Direct Imaging of Laser-driven Ultrafast Molecular Rotation
Published on: February 4, 2017
Observation of a simple vibrational wavepacket in a polyatomic molecule via time-resolved photoelectron velocity-map
Chris J Hammond1, Katharine L Reid, Kate L Ronayne
1School of Chemistry, University of Nottingham, Nottingham NG7 2RD, United Kingdom.
Abstract:
We have prepared a coherent superposition of the two components of a Fermi resonance in the S1 state of toluene at approximately 460 cm(-1) with a approximately 1 ps laser pulse and monitored time-resolved photoelectron velocity-map images. The photoelectron intensities oscillate with time in a manner that depends on their kinetic energy, even though full vibrational resolution in the cation is not achieved. Analysis of the time-dependent photoelectron spectra enables information on the composition of the S1 wavepacket to be deduced. Such an experiment, in which a whole set of partially dispersed cation vibrational states are detected simultaneously, suggests an efficient method of studying intramolecular vibrational energy redistribution processes in excited states.
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