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Updated: Aug 8, 2025
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Dissolution Dynamic Nuclear Polarization Instrumentation for Real-time Enzymatic Reaction Rate Measurements by NMR
Published on: February 23, 2016
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Singlet fission as a polarized spin generator for dynamic nuclear polarization
Yusuke Kawashima1, Tomoyuki Hamachi1, Akio Yamauchi1
1Department of Applied Chemistry, Graduate School of Engineering, 744 Moto-oka, Nishi-ku, Fukuoka, 819-0395, Japan.
Nature Communications
|March 1, 2023
Summary
Singlet fission generates spin-polarized quintet states in organic materials. This spin polarization enhances magnetic resonance sensitivity in water molecules via dynamic nuclear polarization, opening new bio-quantum technology applications.
Area of Science:
- Organic materials science
- Quantum spin dynamics
- Bio-quantum technology
Background:
- Singlet fission (SF) converts singlet excited states to triplet pairs.
- SF is explored for photovoltaics but its spin properties are underutilized.
- Spin polarization is key to advanced magnetic resonance techniques.
Purpose of the Study:
- To demonstrate singlet fission's potential for generating polarized spins.
- To utilize SF-generated quintet spins for enhancing magnetic resonance sensitivity.
- To explore SF applications in bio-quantum technology.
Main Methods:
- Forming supramolecular assemblies of pentacene chromophores.
- Utilizing SF-born quintet multiexcitons for dynamic nuclear polarization (DNP).
- Investigating DNP enhancement in a water-glycerol matrix.
Main Results:
- Achieved dynamic nuclear polarization of water molecules using SF-generated quintet spins.
- Demonstrated improved magnetic resonance sensitivity.
- Observed dependence of nuclear polarization enhancement on magnetic field and microwave power.
Conclusions:
- Singlet fission can serve as a source of polarized spins.
- SF-based DNP enhances magnetic resonance of biological matrices.
- This work pioneers SF applications in bio-quantum technology.
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