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Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
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Understanding electronically non-adiabatic relaxation dynamics in singlet fission
Guohua Tao1,2
1Shenzhen Key Laboratory of New Energy Materials by Design, Peking University , Shenzhen 518055, China.
Journal of Chemical Theory and Computation
|November 18, 2015
Summary
Singlet fission dynamics, crucial for next-gen solar cells, were simulated using symmetrical quasi-classical (SQC) nonadiabatic molecular dynamics (MD). This method offers accurate, real-time insights into the nonadiabatic relaxation process.
Area of Science:
- Photochemistry
- Materials Science
- Computational Chemistry
Background:
- Singlet fission is a key process for enhancing solar cell efficiency.
- Understanding nonadiabatic relaxation from singlet to triplet states is vital for designing efficient solar cells.
Purpose of the Study:
- To investigate the real-time singlet fission dynamics using a novel simulation approach.
- To explore the influence of energy levels, electronic couplings, and electronic-phonon couplings on nonadiabatic relaxation.
Main Methods:
- Symmetrical quasi-classical (SQC) nonadiabatic molecular dynamics (MD) simulations were employed.
- The model system's fission dynamics were studied in real-time.
- Results were compared with analytical approximations like Förster and Marcus theories.
Main Results:
- The SQC nonadiabatic MD simulation accurately describes singlet fission dynamics.
- The method provides microscopic insights into the nonadiabatic relaxation process.
- The dependence of dynamics on various system parameters was examined.
Conclusions:
- SQC nonadiabatic MD simulations are efficient and accurate for studying singlet fission.
- This approach offers valuable microscopic understanding for designing improved solar cells.
- The study highlights the importance of considering electronic and vibronic couplings in singlet fission.
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