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10:35
Novel Techniques for Observing Structural Dynamics of Photoresponsive Liquid Crystals
Published on: May 29, 2018
Transient X-ray fragmentation: probing a prototypical photoinduced ring opening
Vladimir S Petrović1, Marco Siano, James L White
1Department of Physics, Stanford University, Stanford, California 94305, USA. petrovic@stanford.edu
Physical Review Letters
|September 26, 2012
Summary
This study uses X-ray lasers to observe UV-induced photoisomerization in real-time. We found that ion fragmentation patterns change over time as the molecule transforms, offering new insights into molecular dynamics.
Area of Science:
- Physical Chemistry
- Ultrafast Spectroscopy
- Molecular Dynamics
Background:
- Photoisomerization is a fundamental process in molecular science.
- Understanding molecular transformations requires time-resolved studies.
- X-ray lasers offer new possibilities for probing ultrafast events.
Purpose of the Study:
- To investigate UV-induced photoisomerization using core ionization by an X-ray laser.
- To study X-ray ionization and fragmentation of the cyclohexadiene-hexatriene system during ring opening.
- To explore the temporal evolution of molecular states and geometry.
Main Methods:
- Utilizing an X-ray laser at 850 eV for core ionization.
- Probing the cyclohexadiene-hexatriene system during UV-induced ring opening.
- Analyzing ion-fragmentation patterns and kinetic energies over picoseconds.
Main Results:
- Observed evolution of ion-fragmentation patterns over a picosecond timescale.
- Found that kinetic energy per ion fragment and H(+) ion count increase during ring opening and molecular elongation.
- Demonstrated a correlation between molecular geometry changes and fragmentation patterns.
Conclusions:
- Ion fragmentation provides insights into the dynamic changes during photoisomerization.
- X-ray probe experiments reveal ultrafast molecular dynamics.
- Optical pump X-ray probe techniques open new avenues in molecular photophysics.
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