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Updated: May 14, 2026
08:22
Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
Attosecond-recollision-controlled selective fragmentation of polyatomic molecules
Xinhua Xie1, Katharina Doblhoff-Dier, Stefan Roither
1Photonics Institute, Vienna University of Technology, A-1040 Vienna, Austria.
Physical Review Letters
|February 2, 2013
Summary
Scientists precisely control molecular fragmentation using intense laser pulses. The optical waveform dictates electron wave packet energy, enabling selective control over reactions in polyatomic molecules.
Area of Science:
- Physical Chemistry
- Quantum Mechanics
- Molecular Dynamics
Background:
- Controlling chemical reactions at the molecular level is a key challenge in chemistry.
- Understanding fragmentation reactions is crucial for chemical synthesis and analysis.
Purpose of the Study:
- To demonstrate experimental control over molecular fragmentation reactions using intense few-cycle laser pulses.
- To investigate the mechanism of fragmentation induced by laser-molecule interactions.
Main Methods:
- Experimental manipulation of the optical waveform of intense few-cycle laser pulses.
- Theoretical modeling of electron wave packet dynamics and inelastic ionization.
- Study of polyatomic molecules like acetylene, ethylene, and 1,3-butadiene.
Main Results:
- Precise control over fragmentation reactions of polyatomic molecules was achieved.
- The mechanism involves inelastic ionization from inner-valence molecular orbitals by recolliding electron wave packets.
- Recollision energy is highly dependent on the laser pulse's optical waveform.
Conclusions:
- The optical waveform of intense few-cycle laser pulses offers an efficient and selective method for controlling molecular fragmentation.
- Subfemtosecond control over fragmentation and isomerization reactions in polyatomic molecules is possible.
- This approach opens new avenues for ultrafast chemistry and molecular manipulation.
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