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Geometric Evolution of Perylene-Based Intermolecular π-π Dimers Toward Static and Dynamic Multicolor Emission
Zhou-An Xia1, Min Wu2, Yuxiang Dai3
1State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, China.
Angewandte Chemie (International Ed. in English)
|June 18, 2026
Summary
Researchers designed a new organic solid capable of emitting multiple colors by controlling molecular arrangements. This breakthrough offers insights into creating advanced optical materials by tuning pi-pi interactions in dimers.
Area of Science:
- Materials Science
- Organic Chemistry
- Photophysics
Background:
- Achieving controllable multicolor emission from single-molecule-based organic solids is challenging due to complex molecular packing.
- Understanding and controlling intermolecular interactions, particularly pi-pi stacking, is crucial for tuning photophysical properties.
Purpose of the Study:
- To design and synthesize a novel organic compound capable of exhibiting multicolor emission by precisely controlling pi-pi dimer geometries.
- To investigate the relationship between molecular packing, intermolecular interactions, and emission color in organic solids.
- To explore the potential for developing intelligent optical materials through polymorphism, piezochromism, and thermochromism.
Main Methods:
- Synthesis of 3-(4-(1,2,2-triphenylvinyl)phenyl)perylene (pTPE-PE), integrating a perylene (PE) core with a tetraphenyl ethylene (TPE) substituent.
- Crystallization of pTPE-PE to obtain multiple polymorphs with distinct emission colors.
- Investigation of pressure-induced (piezochromism) and temperature-induced (thermochromism) emission changes.
- Analysis of pi-pi stacking interactions, interplanar distances, and overlap ratios within the dimers.
Main Results:
- pTPE-PE crystallization yielded four polymorphs emitting green, yellow, orange, and red light, demonstrating static multicolor emission.
- Emission color was directly correlated with pi-pi interactions: closer interplanar distances and larger overlap ratios resulted in red-shifted emission.
- Dynamic multicolor transitions were observed: yellow to orange to red under pressure, and sky-blue to green to orange with thermal stimuli.
- Polymorphism, piezochromism, and thermochromism provided experimental evidence for exciton modulation via the dimer model.
Conclusions:
- Tailoring pi-pi dimer geometries is an effective strategy for achieving controllable multicolor emission in organic solids.
- The designed pTPE-PE compound serves as a model system for understanding exciton modulation through supramolecular interactions.
- This study offers valuable insights for the rational design of intelligent optical materials with tunable emission properties.
Keywords:
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