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Updated: Mar 22, 2026

Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
Ultrafast Bimolecular Reaction in Acetylene Dimer Induced by Femtosecond Strong-Laser-Field Ionization
Junyang Ma1, Enliang Wang2, Zhubin Hu1
1East China Normal University, State Key Laboratory of Precision Spectroscopy, Shanghai 200241, China.
Strong laser fields induce a bimolecular reaction in acetylene dimers, forming new isomers. Delayed ionization triggers fragmentation, revealing ultrafast chemical dynamics in molecular systems.
Area of Science:
- Physical Chemistry
- Chemical Physics
- Femtochemistry
Background:
- Acetylene dimer ((C2H2)2) is a fundamental weakly bound molecular system.
- Strong laser fields can initiate complex chemical transformations.
Purpose of the Study:
- To investigate strong laser field-driven bimolecular reactions in acetylene dimers.
- To elucidate the reaction pathway and timescale using time-resolved techniques.
Main Methods:
- Femtosecond strong laser field ionization.
- Time-resolved fragment analysis.
- Molecular dynamics simulations.
Main Results:
- Observation of a femtosecond strong-laser-field-ionization-induced bimolecular reaction in (C2H2)2.
- Formation of a C4H4+ isomer via ultrafast intermolecular rearrangement.
- Subpicosecond multistep reaction pathway involving hydrogen migration and C-C reorganization.
- Fragmentation into CH3+ and C3H+ following delayed ionization.
Conclusions:
- Strong laser fields can drive bimolecular reactions in hydrocarbon dimers.
- Time-delayed ionization is a viable method for controlling chemical reactivity.
- Ultrafast bond formation and structural reorganization occur on subpicosecond timescales.
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