Temperature-dependent assemblies from a 2-D triple-stranded meso-helical layer to a 3-D chain-layer metal-organic...

Area of Science:

• Coordination Chemistry
• Materials Science
• Luminescence

Background:

• Dysprosium (Dy) based coordination polymers are explored for their unique structural and functional properties.
• Multidentate ligands like 2,6-dimethylpyridine-3,5-dicarboxylic acid (H2mpda) offer versatile coordination possibilities.

Purpose of the Study:

• To synthesize and characterize novel dysprosium coordination polymers.
• To investigate the luminescent and gas sorption properties of the synthesized materials.

Main Methods:

• Hydrothermal synthesis of dysprosium coordination polymers.
• Single-crystal X-ray diffraction for structural analysis.
• Fluorescence spectroscopy for luminescence studies.
• Gas adsorption analysis for sorption properties.

Main Results:

• Two distinct crystal forms, {[Dy2(mpda)3(H2O)2]·H2O}n (1) and [Dy2(mpda)3(H2O)4]n (2), were successfully synthesized.
• Compound 1 exhibits a 2-D triple-stranded meso-helical layer structure, while compound 2 forms a 3-D chain-layer framework.
• Compound 1 demonstrates "on-off" luminescence switching, indicating its potential as a metal ion probe, and shows notable hydrogen sorption capacity.

Conclusions:

• The study successfully synthesized and characterized two novel dysprosium coordination polymers with different dimensionalities.
• Compound 1 shows significant potential as a luminescent sensor for metal ions and possesses hydrogen storage capabilities.
• The unique structural features, including 4-aza bowl-like crown ethers, are crucial for the observed luminescence properties.