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Updated: Jan 14, 2026
06:44
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
69.6K
Crystal engineering enables room-temperature triplet-DNP in cocrystals.
Haruki Sato1, Makoto Negoro2,3,4, Akinori Kagawa2,3
1Graduate School of Science and Technology for Innovation, Tokushima University, Tokushima 770-8506, Japan.
Chemical Communications (Cambridge, England)
|October 27, 2025
Summary
Crystal engineering creates new polarization materials for room-temperature triplet-dynamic nuclear polarization (triplet-DNP). This method enhances aliphatic dicarboxylic acid polarization for advanced NMR and MRI applications.
Area of Science:
- Solid-state chemistry
- Nuclear magnetic resonance spectroscopy
- Hyperpolarization techniques
Background:
- Dynamic nuclear polarization (DNP) enhances NMR sensitivity.
- Triplet-DNP offers unique polarization pathways.
- Room-temperature DNP remains a challenge for many molecules.
Purpose of the Study:
- To develop crystal engineering strategies for room-temperature triplet-DNP.
- To enable triplet-DNP of aliphatic dicarboxylic acids.
- To expand the scope of molecules amenable to hyperpolarization.
Main Methods:
- Cocrystal design using nicotinamide as a coformer.
- Utilizing hydrogen bonding and π-π interactions for rigid frameworks.
- Characterization of cocrystal properties for spin diffusion.
Main Results:
- Demonstrated successful crystal engineering of polarization matrices.
- Achieved room-temperature triplet-DNP for aliphatic dicarboxylic acids.
- Maintained long spin-lattice relaxation times (T1) via rigid molecular structures.
Conclusions:
- Crystal engineering is a viable strategy for developing novel DNP materials.
- Room-temperature triplet-DNP is achievable through rational cocrystal design.
- Expanded applicability of hyperpolarization in NMR and MRI.
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