Monomer and Excimer Emission in a Conformational and Stacking-Adaptable Molecular System

Area of Science:

• Materials Science
• Organic Chemistry
• Photophysics

Background:

• Developing single-platform luminous materials with tunable emission properties is crucial for advanced optical applications.
• Controlling molecular conformation and intermolecular interactions is key to modulating fluorescence output.

Purpose of the Study:

• To design donor-acceptor-π molecules with adaptable conformations and stacking behaviors.
• To achieve precise regulation of monomer and excimer emissions on a single platform.
• To explore temperature-responsive fluorescence for sensing and encryption.

Main Methods:

• Molecular design incorporating conformation, alkyl chain length, and charge-transfer.
• Synthesis of donor-acceptor-π type molecules.
• Investigation of fluorescence properties in dispersed and crystalline states.
• Utilizing a phase-change fatty acid matrix for environmental responsiveness.

Main Results:

• Achieved bright monomer emission in dispersed states due to planar conformations.
• Induced strong intermolecular interactions and staggered π-π stacking in crystalline states, leading to bright excimer emission.
• Demonstrated reversible switching between dispersed and aggregated states in a fatty acid matrix.
• Exhibited temperature-responsive fluorescence.

Conclusions:

• The developed molecular design strategy enables precise control over monomer and excimer emission.
• The molecules exhibit tunable fluorescence based on conformational and aggregation states.
• The temperature-responsive fluorescence has potential in advanced monitoring and information encryption systems.