Proton-coupled energy transfer in molecular triads
Belinda Pettersson Rimgard1, Zhen Tao2, Giovanny A Parada2,3
1Department of Chemistry - Ångström Laboratory, Uppsala University, SE 75120 Uppsala, Sweden.
Science (New York, N.Y.)
|July 21, 2022
Summary
Researchers discovered proton-coupled energy transfer (PCEnT), a novel photochemical mechanism. This process enables energy transfer between molecules with non-overlapping spectra, relevant for biology and photonics.
Area of Science:
- Photochemistry
- Molecular mechanisms
- Energy transfer
Background:
- Excited-state dynamics in molecular systems.
- Energy transfer mechanisms in organic molecules.
- Role of proton transfer in photochemical reactions.
Purpose of the Study:
- To experimentally discover and theoretically analyze a novel photochemical mechanism termed proton-coupled energy transfer (PCEnT).
- To investigate the energy transfer process in anthracene-phenol-pyridine triads.
- To explore the implications of PCEnT for biological systems and photonic devices.
Main Methods:
- Experimental photochemical studies using light excitation at ~400 nm.
- Theoretical calculations to analyze energy transfer and charge transfer.
- Spectroscopic analysis of fluorescence and absorption properties.
Main Results:
- Discovery of proton-coupled energy transfer (PCEnT) in anthracene-phenol-pyridine triads.
- Observation of singlet-singlet energy transfer from anthracene to phenol-pyridine despite lack of spectral overlap.
- Demonstration that coupled proton transfer lowers excited-state energy, facilitating energy acceptance.
- Theoretical confirmation of negligible charge transfer between molecular units.
Conclusions:
- PCEnT is a novel photochemical mechanism.
- PCEnT enables efficient energy transfer between molecules with non-overlapping spectra.
- The mechanism has potential relevance for biological systems and the development of photonic devices.
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