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Environment-dependent ultrafast photoisomerization dynamics in azo dye
Chun-Chih Hsu1, Yu-Ting Wang, Atsushi Yabushita
1Department of Electrophysics, National Chiao-Tung University, Hsinchu, Taiwan, Republic of China.
The Journal of Physical Chemistry. A
|September 16, 2011
Summary
Disperse Red 19, an azoaromatic dye, undergoes ultrafast photoisomerization. Its dynamics differ in solution versus film, showing the molecular environment
Area of Science:
- Materials Science
- Photochemistry
- Spectroscopy
Background:
- Azoaromatic dyes are crucial for optical devices due to ultrafast photoisomerization.
- Disperse Red 19 is a notable azobenzene nonlinear optical chromophore with a high ground-state dipole moment.
Purpose of the Study:
- To investigate the ultrafast photoisomerization dynamics of a push-pull substituted azobenzene dye, Disperse Red 19.
- To understand how the molecular environment influences these dynamics.
Main Methods:
- Ultrafast time-resolved spectroscopy was employed.
- The study analyzed Disperse Red 19 in both solution and film states.
Main Results:
- Distinct ultrafast dynamics were observed between solution and film samples.
- The molecular environment significantly impacts the photoisomerization process of Disperse Red 19.
Conclusions:
- The study clarifies the photoisomerization dynamics of Disperse Red 19.
- Environmental factors play a critical role in the dye's photophysical behavior, relevant for optical device applications.
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