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Updated: Dec 31, 2025
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From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
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Halogen Bonding Facilitates Intersystem Crossing in Iodo-BODIPY Chromophores
Yumin Lee1, Roy M Malamakal1, David M Chenoweth1
1University of Pennsylvania , 231 South 34 Street , Philadelphia , Pennsylvania 19104 United States.
The Journal of Physical Chemistry Letters
|January 15, 2020
Summary
Halogen bonding enhances triplet state formation in diiodo-BODIPY molecules. This discovery advances organic triplet photosensitizers for solar energy and photodynamic therapy applications.
Area of Science:
- Organic chemistry
- Photochemistry
- Supramolecular chemistry
Background:
- BODIPY chromophores are versatile organic-based triplet photosensitizers.
- Efficient triplet state formation is crucial for photosensitizer applications.
- Modulating triplet state formation can enhance performance in solar energy and photodynamic therapy.
Purpose of the Study:
- To investigate the role of halogen bonding in facilitating intersystem crossing (ISC) in diiodo-BODIPY.
- To understand how noncovalent solvent interactions influence triplet state formation.
Main Methods:
- Ultrafast transient absorption spectroscopy was used to study diiodo-BODIPY.
- Experiments were conducted in the presence of pyridine-based halogen bonding solvents.
- Quantum chemical calculations were employed to interpret the results.
Main Results:
- Halogen bonding was found to significantly increase the intersystem crossing rate constant of diiodo-BODIPY.
- This facilitation enhances the formation of the triplet state.
- Quantum chemical calculations revealed that halogen bonding modifies spin-orbit coupling and alters singlet-triplet energy levels.
Conclusions:
- Halogen bonding is an effective strategy to enhance intersystem crossing in BODIPY-based photosensitizers.
- This work provides insights into modulating triplet state dynamics for improved applications.
- The findings support the application of Marcus theory in understanding ISC processes influenced by noncovalent interactions.
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