Structural diversity and solvent-induced transformations of a copper-based metal-organic framework with highly...

Area of Science:

• Materials Science
• Crystallography
• Supramolecular Chemistry

Background:

• Metal-organic frameworks (MOFs) are advanced porous materials with tunable structures.
• Tetracarboxylate ligands are crucial building blocks for constructing diverse MOF architectures.
• Understanding solvent-induced transformations is key to MOF stability and functionality.

Purpose of the Study:

• To synthesize and characterize novel copper-based MOFs using a new tetracarboxylic acid ligand.
• To investigate the solvent-induced structural transformations of these MOFs.
• To explore the crystalline-to-amorphous phase transitions in MOFs.

Main Methods:

• Synthesis of copper-based MOFs using 5,5'-([9,9'-bianthracene]-10,10'-diyl)diisophthalic acid (H4BADI).
• Single-crystal X-ray diffraction for structural analysis.
• Solvent exchange experiments to induce structural transformations.

Main Results:

• A series of copper-based MOFs, [Cu2(BADI)(S)2]·xS, were successfully prepared.
• Single-crystal-to-single-crystal transformations were observed upon solvent exchange (e.g., DMF to DMSO).
• Reversible crystalline-to-amorphous phase transformations were achieved with volatile, polar solvents.

Conclusions:

• The newly designed ligand H4BADI enables the formation of MOFs with dynamic structural properties.
• Solvent-induced transformations, including reversible crystalline-to-amorphous transitions, are characteristic of these copper-based MOFs.
• These findings contribute to the understanding of MOF flexibility and potential applications in responsive materials.