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Updated: Apr 8, 2026
06:53
Photoelectron Imaging of Anions Illustrated by 310 Nm Detachment of F−
Published on: July 27, 2018
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Quantitative Intramolecular Singlet Fission in Bipentacenes
Samuel N Sanders1, Elango Kumarasamy1, Andrew B Pun1
1†Department of Chemistry, Columbia University, New York, New York 10027, United States.
Journal of the American Chemical Society
|June 24, 2015
Summary
Singlet fission (SF) in bipentacenes achieves high triplet yields in dilute solutions, demonstrating intramolecular SF as an intrinsic molecular property. This breakthrough could boost solar cell efficiency beyond current limits.
Area of Science:
- Photophysics and Photochemistry
- Materials Science
- Renewable Energy Technologies
Background:
- Singlet fission (SF) can theoretically increase single-junction solar cell efficiency from 33% to 44%.
- Previously, high SF yields were limited to crystalline solids or oligoacene aggregates.
- Efficient SF in dilute solutions has remained a significant challenge.
Purpose of the Study:
- To demonstrate and quantify intramolecular singlet fission (iSF) in bipentacene molecules.
- To investigate the role of molecular structure and electronic coupling in iSF.
- To explore the potential of iSF for enhancing solar energy conversion.
Main Methods:
- Transient absorption spectroscopy
- Ultrafast photoluminescence spectroscopy
- Triplet photosensitization studies
Main Results:
- Achieved triplet yields approaching 200% per absorbed photon in bipentacenes via iSF.
- Demonstrated that iSF occurs in dilute solutions, independent of intermolecular interactions.
- Correlated triplet pair lifetime (0.5–270 ns) with the electronic coupling between pentacene units.
Conclusions:
- Intramolecular singlet fission is an intrinsic property of bipentacenes, controllable by molecular design.
- iSF in solution offers a viable pathway to overcome SF limitations in solid-state devices.
- This work paves the way for developing next-generation solar cells with significantly enhanced efficiency.
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