Tetrahedral onsager crosses for solubility improvement and crystallization bypass

Area of Science:

• Materials Science
• Organic Chemistry
• Solid-State Chemistry

Background:

• Pure organic molecules with concave rigid shapes can form porous glasses.
• This property offers potential for preventing crystallization and enhancing solubility.
• High internal energy in solid phases is a key characteristic.

Purpose of the Study:

• To quantitatively explore the strategy of improving molecular solubility using rigid molecular structures.
• To synthesize and investigate a series of rigid tetrahedral conjugated molecules (nC) and their models (nR).

Main Methods:

• Synthesis of rigid tetrahedral conjugated molecules (nC) and model compounds (nR).
• Characterization using UV absorption and fluorescence emission spectroscopy.
• Thermal analysis via differential scanning calorimetry.
• Solid-state and diffusion studies using NMR spectroscopy ((1)H and (13)C MAS).
• Film thickness analysis using multiple-beam interferometry.

Main Results:

• Tetrahedral cross molecules exhibit up to 8 orders of magnitude higher solubility than model compounds.
• Concentrated monomeric solutions were achieved.
• Homogeneous films with nanometer-scale thickness were successfully deposited on surfaces.

Conclusions:

• Cross-like molecular architectures significantly enhance solubility compared to linear models.
• The ability to form concentrated monomeric solutions facilitates thin film deposition.
• These molecular designs show promise for diverse applications requiring porous materials and thin films.