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Updated: May 5, 2026
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Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
Published on: May 27, 2020
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The structure and dynamics of molecular excitons
1Department of Chemistry, University of California, Riverside, California 92521;
Annual Review of Physical Chemistry
|December 10, 2013
Summary
This review classifies exciton types in organic semiconductors, including Frenkel singlet, Frenkel triplet, and charge transfer excitons. It explores their photophysical behavior, experimental challenges, and multiexciton processes like singlet fission for solar energy applications.
Area of Science:
- Materials Science
- Physical Chemistry
- Organic Electronics
Background:
- Excitonic states govern organic semiconductor photophysics.
- Understanding exciton behavior is crucial for device applications.
- Solid-state organic systems present unique experimental challenges.
Purpose of the Study:
- To classify and review exciton types in organic semiconductors.
- To discuss experimental challenges in studying these systems.
- To explore multiexciton processes and their applications.
Main Methods:
- Classification of exciton types: Frenkel singlet, Frenkel triplet, charge transfer.
- Discussion of steady-state spectroscopy and exciton diffusion models.
- Analysis of multiexciton processes (singlet fission, triplet fusion).
Main Results:
- Energetic disorder in disordered matrices leads to subdiffusive exciton motion.
- Singlet fission and triplet fusion involve spin state coherence and magnetic fields.
- Singlet fission demonstrates exciton interactions for solar energy conversion.
Conclusions:
- Exciton classification and understanding are key to organic semiconductor photophysics.
- Multiexciton processes offer pathways for advanced applications like solar energy.
- Further research into exciton dynamics can drive innovation in organic electronics.
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