Bis(tricyclic) Aromatic Enes That Exhibit Efficient Fluorescence in the Solid State

Area of Science:

• Organic Chemistry
• Materials Science
• Photophysics

Background:

• Organic luminophores are crucial for optoelectronic devices.
• Developing novel materials with high fluorescence quantum yields is an ongoing challenge.

Purpose of the Study:

• To synthesize and characterize a new class of bis(tricyclic) aromatic enes (BAEs).
• To investigate the photophysical properties of BAEs in solid-state and polymer films.
• To explore the potential of BAEs as efficient organic luminophores.

Main Methods:

• Palladium-catalyzed double cross-coupling reactions were employed for BAE synthesis.
• Photophysical properties, including fluorescence quantum yields, were measured.
• Density functional theory (DFT) calculations were performed to understand optical excitation mechanisms.

Main Results:

• Synthesized BAEs based on acridine, xanthene, thioxanthene, and thioxanthene-S,S-dioxide frameworks.
• BAEs exhibited blue-to-green fluorescence with good to excellent quantum yields (Φ = 0.45-0.88) in solid-state samples.
• Dispersing BAEs in poly(methyl methacrylate) (PMMA) films enhanced emission efficiency (Φ = 0.59-0.91).

Conclusions:

• Bis(tricyclic) aromatic enes represent a promising new class of organic luminophores.
• BAEs demonstrate high fluorescence efficiency in both solid-state and polymer film formats.
• DFT calculations provide insights into the electronic transitions governing BAEs' optical properties.