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06:53
Photoelectron Imaging of Anions Illustrated by 310 Nm Detachment of F−
Published on: July 27, 2018
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Effect of high-frequency modes on singlet fission dynamics
Yuta Fujihashi1, Lipeng Chen1, Akihito Ishizaki2
1Division of Materials Science, Nanyang Technological University, Singapore 639798, Singapore.
The Journal of Chemical Physics
|February 3, 2017
Summary
Singlet fission, a process boosting organic solar cell efficiency, is significantly influenced by molecular vibrations. Understanding these vibrations is key to optimizing energy conversion.
Area of Science:
- Organic electronics
- Photovoltaics
- Quantum dynamics
Background:
- Singlet fission converts one high-energy singlet excitation into two lower-energy triplet excitations.
- This process holds potential for significantly enhancing organic photovoltaic (OPV) efficiency.
- High-frequency intramolecular vibrations are crucial for efficient singlet fission in pentacene derivatives.
Purpose of the Study:
- To investigate the impact of vibration-induced fluctuations on singlet fission dynamics.
- To explore the role of single and multiple intramolecular vibrational modes in singlet fission.
Main Methods:
- Quantum dynamics calculations were employed.
- Parameters were derived from fitting measured linear and nonlinear spectra of pentacene derivatives.
- The influence of one and two vibrational modes on fission dynamics was examined.
Main Results:
- Singlet fission dynamics are strongly dependent on the frequency of the intramolecular vibrational mode.
- Including a second vibrational mode introduces an additional fission channel, even with a small Huang-Rhys factor.
- Additional vibrational modes can alter the interplay with the dominant vibrational mode, affecting overall fission dynamics.
Conclusions:
- Molecular vibrations play a critical role in modulating singlet fission efficiency.
- The frequency and number of vibrational modes significantly influence the pathways and dynamics of singlet fission.
- This research provides insights for designing materials with enhanced singlet fission properties for OPV applications.
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