Multidimensional Structure Conformation of Persulfurated Benzene for Highly Efficient Phosphorescence

Area of Science:

• Materials Science
• Organic Chemistry
• Photophysics

Background:

• Developing highly emissive phosphorescent molecules is challenging.
• Molecular conformation and crystal packing significantly influence photophysical properties.

Purpose of the Study:

• To investigate the relationship between molecular conformation, crystal growth, and phosphorescence efficiency in persulfurated benzene compounds.
• To provide insights for designing novel phosphorescent materials.

Main Methods:

• Synthesis of persulfurated benzene compounds with varying peripheral groups.
• Control of molecular conformation and crystal growth modes (1D, 2D, 3D).
• Photophysical characterization and theoretical calculations (DFT).

Main Results:

• A symmetrical 3,3-conformer adopted a 3D crystal growth mode, exhibiting high phosphorescence efficiency.
• The 3D crystal structure and a bright boat-like triplet state (T1) contributed to efficient emission.
• Unsymmetrical 2,4-conformers formed 1D/2D crystals with weak emission due to nonradiative decay pathways.

Conclusions:

• Molecular conformation and crystal engineering are crucial for enhancing phosphorescence.
• The 3D crystal growth and specific molecular geometry (3,3-conformer) are key for high emission.
• This work offers a strategy for designing efficient phosphorescent materials.