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Updated: Jun 19, 2026
09:34
Synthesis of Information-bearing Peptoids and their Sequence-directed Dynamic Covalent Self-assembly
Published on: February 6, 2020
Supersaturation-controlled assembly pathway directs hierarchical chirality expression in ionic luminophores.
Qiong Wang1,2, Haidi Liu1,2, Ruyuan Zhang1,2
1Key Laboratory of Photochemistry, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry Chinese Academy of Sciences, Beijing 100190, China.
Summary
Controlling molecular chirality in synthetic materials is challenging. This study reveals how supersaturation dynamics during antisolvent diffusion guide chiral assembly, enabling distinct macroscopic chiral structures with tunable chiroptical properties.
Area of Science:
- Materials Science
- Supramolecular Chemistry
- Physical Chemistry
Background:
- Controlled expression of molecular chirality is crucial for natural assemblies but difficult in synthetic materials.
- Chirality dictates the function and properties of many biological and synthetic systems.
Purpose of the Study:
- To investigate the role of supersaturation dynamics in directing chiral expression during antisolvent diffusion.
- To explore how tuning diffusion conditions influences chiral assembly pathways and chiroptical properties.
Main Methods:
- Utilized antisolvent diffusion to control supersaturation levels and temporal evolution.
- Analyzed two distinct assembly pathways emerging from ion-paired luminophores.
- Characterized the chiroptical properties, including circularly polarized light emission (CPLE) dissymmetry factors (|gCPLE|), of the resulting materials.
Main Results:
- Nucleation initiates at a critical supersaturation threshold, followed by divergent growth pathways.
- Rapid antisolvent diffusion leads to vortex-like films with strong chiral organization and high |gCPLE| values due to scattering.
- Sustained supersaturation yields square microcrystals with weak supramolecular chirality and low |gCPLE|.
- Two pathways produce distinct chiroptical signatures with opposite CPLE signs and varied magnitudes.
Conclusions:
- Established a mechanistic link between supersaturation evolution and hierarchical chiral assembly.
- Demonstrated the ability to direct chiral expression and tune chiroptical responses by controlling diffusion kinetics.
- Provided insights for designing macroscopic chiral photonic architectures for biomimetic and chiroptical applications.
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