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Published on: August 15, 2018
A flexible coordination polymer crystal providing reversible structural and magnetic conversions
Wakako Kaneko1, Masaaki Ohba, Susumu Kitagawa
1Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto, Japan.
Journal of the American Chemical Society
|October 13, 2007
Summary
This study introduces a flexible coordination polymer with removable water molecules. This material exhibits reversible structural and magnetic changes in response to environmental stimuli, demonstrating potential for responsive applications.
Area of Science:
- Materials Science
- Inorganic Chemistry
- Crystallography
Background:
- Coordination polymers are known for structural flexibility and environmental responsiveness.
- Designing materials with tunable properties is crucial for advanced applications.
Purpose of the Study:
- To synthesize and characterize a novel 2D cyanide-bridged Mn(II)Cr(III) coordination polymer.
- To investigate the structural, magnetic, and adsorption properties of the material and its dehydrated form.
- To explore the potential of this material for stimuli-responsive applications.
Main Methods:
- Single-crystal X-ray diffraction to determine structures.
- Variable-temperature magnetic susceptibility measurements.
- Gas/solvent adsorption/desorption studies.
Main Results:
- A 2D coordination polymer, [Mn(NNdmenH)(H2O)][Cr(CN)6].H2O (1), was synthesized.
- Reversible single-crystal-to-single-crystal transformation between 2D and 3D frameworks (1a) upon dehydration/hydration.
- Ferrimagnetic ordering observed at 35.2 K (1) and 60.4 K (1a), reversibly modulated by guest exchange.
- Dehydrated 1a showed size-selective solvent adsorption and framework shrinkage/expansion.
Conclusions:
- The synthesized coordination polymer exhibits significant structural flexibility and stimuli-responsive magnetic behavior.
- Removable water coligands facilitate reversible structural and magnetic transitions.
- The material demonstrates potential for applications in sensing and separation technologies due to its responsive framework and selective adsorption capabilities.
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