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Frank-Kasper phases in charge transfer complexes enable tunable photoelectronic properties
Xinyue Zhao1, Chenhui Wei1, Wang Fuzhou1
1Information Recording Materials Lab, Beijing Key Laboratory of Printing & Packaging Materials and Technology, Beijing Institute of Graphic Communication, Beijing, 102600, China. zhangchunxiu@bigc.edu.cn.
Soft Matter
|June 21, 2024
Summary
Researchers observed the Frank-Kasper (F-K) phase in discotic liquid crystals for the first time. This complex spherical packing, formed by charge transfer complexes, creates novel self-assembled nanostructures.
Area of Science:
- Soft matter physics
- Materials science
- Crystallography
Background:
- Understanding particle packing and symmetry selection in soft matter is complex.
- The Frank-Kasper (F-K) phase, a form of complex spherical packing, has not been previously observed in discotic liquid crystals.
Purpose of the Study:
- To report the first observation of F-K phases in discotic liquid crystals.
- To characterize the self-assembly of charge transfer complexes (CTCs) into F-K phases.
Main Methods:
- Synthesis of charge transfer complexes (CTCs) from triphenylene derivatives and 2,4,7-trinitro-9-fluorenone.
- Experimental characterization of the CTCs.
- Theoretical calculations to determine lattice structure.
Main Results:
- First observation of F-K phases in discotic liquid crystals.
- Characterization of an F-K A15 cubic lattice with a small lattice constant (3.2 nm).
- Unit cell contains 8 sphere-like supramolecules, each self-assembled from 3 CTC complexes.
- Supramolecular assembly leads to isolated spherical fragments, impeding charge transfer and creating an insulator.
Conclusions:
- Demonstration of F-K phases in discotic liquid crystals using CTCs.
- Smallest observed A15 lattice constant for this phase.
- Method provides a route to asymmetric complex compounds for novel nanostructures.
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