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Updated: May 7, 2026

Direct Imaging of Laser-driven Ultrafast Molecular Rotation
Published on: February 4, 2017
Ultrafast imaging of electronic relaxation in o-xylene: a new competing intersystem crossing channel
Yuzhu Liu1, Gregor Knopp, Patrick Hemberger
1Paul Scherrer Institute, 5232 Villigen, Switzerland. yuzhu.liu@psi.ch.
Abstract:
The ultrafast dynamics of the second singlet electronically excited state (S2) in o-xylene was investigated by femtosecond time-resolved photoelectron imaging. A new competing relaxation channel of the S2 state was observed and assigned to the T3 ← S2 intersystem crossing. Interestingly, it is found that the relaxation via this channel occurs on a comparable femtosecond timescale as the S1 ← S2 internal conversion. A lifetime of ~60 fs for the initially excited S2 state, of 540 (±17) fs for the secondary populated S1 state, and of 7.23 (±0.21) ps for the T3 state could be inferred.
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