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Updated: Jun 6, 2026
09:57
Ultrafast Time-resolved Near-IR Stimulated Raman Measurements of Functional π-conjugate Systems
Published on: February 10, 2020
Ultrafast dynamics through conical intersections and intramolecular vibrational energy redistribution in styrene
A D G Nunn1, R S Minns, R Spesyvtsev
1Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, UK.
Physical Chemistry Chemical Physics : PCCP
|November 12, 2010
Summary
Internal conversion in styrene
Area of Science:
- Physical Chemistry
- Molecular Spectroscopy
- Photochemistry
Background:
- Styrene's excited electronic states are crucial for understanding its photochemical behavior.
- Internal conversion is a key non-radiative decay pathway in molecules.
Purpose of the Study:
- To investigate the dynamics of internal conversion in styrene's first two excited singlet states.
- To determine the timescales of radiationless decay through S(1)/S(0) conical intersections.
Main Methods:
- Femtosecond time-resolved photoelectron spectroscopy (TRPES) was employed.
- Direct excitation to S(1) and S(2) states of styrene was performed.
Main Results:
- Radiationless decay via an S(1)/S(0) conical intersection occurs on a ~4 ps timescale after direct S(1) excitation.
- This decay process is significantly slower (~20 ps) following S(2) to S(1) internal conversion.
Conclusions:
- The pathway of excitation significantly impacts the rate of internal conversion in styrene.
- Femtosecond TRPES provides detailed insights into ultrafast non-radiative decay processes.
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