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Updated: Jun 27, 2026
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Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy
Published on: June 27, 2014
Capturing molecular structural dynamics by 100 ps time-resolved X-ray absorption spectroscopy.
Tokushi Sato1, Shunsuke Nozawa, Kohei Ichiyanagi
1Department of Materials Science, Tokyo Institute of Technology, 2-12-1-H61 Ohokayama, Meguro-ku, Tokyo 152-8551, Japan.
Journal of Synchrotron Radiation
|December 20, 2008
Summary
A new experimental setup achieves 100 ps time resolution for time-resolved X-ray absorption spectroscopy. This technique precisely aligns X-ray and laser beams, enabling detailed studies of fast chemical reactions.
Area of Science:
- Physical Chemistry
- Spectroscopy
- Materials Science
Background:
- Time-resolved X-ray absorption spectroscopy (XAS) is crucial for studying ultrafast chemical dynamics.
- Achieving precise spatial and temporal overlap between X-ray and laser pulses is a significant experimental challenge.
Purpose of the Study:
- To present a novel experimental setup for time-resolved XAS with 100 picosecond (ps) resolution.
- To demonstrate a method for stabilizing the X-ray and laser beam overlap at the sample position.
Main Methods:
- Development of an experimental setup at beamline NW14A, Photon Factory Advanced Ring.
- Implementation of X-ray positional active feedback to monochromator crystals.
- Utilizing a figure-of-merit scan for laser beam position optimization.
- Performing time-resolved X-ray absorption fine structure (XAFS) measurements.
Main Results:
- The developed setup achieves a time resolution of 100 ps.
- Active feedback and beam scanning successfully stabilize the spatial overlap of X-ray and laser beams.
- Demonstrated the capability to measure photo-induced spin crossover reactions.
Conclusions:
- The presented experimental setup is effective for high-resolution time-resolved XAS.
- The stabilization technique is essential for accurate measurements of transient species.
- The method allows for the investigation of complex photochemical processes, such as spin crossover reactions.
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