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Updated: Jul 19, 2026
10:52
Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
Published on: July 27, 2022
Coordination polymers undergoing spin crossover and reversible ligand exchange in the solid
Ana Galet1, M Carmen Muñoz, José Antonio Real
1Departament de Física Aplicada, Universitat Politécnica de València, Camino de Vera s/n, 46022, Valencia, Spain.
Chemical Communications (Cambridge, England)
|October 19, 2006
Summary
Researchers synthesized a novel polymer featuring iron(II) ions and gold cyanide bridges. This material reversibly transforms into interpenetrated 3-D frameworks, exhibiting interesting spin crossover properties.
Area of Science:
- Materials Science
- Coordination Chemistry
- Crystallography
Background:
- Coordination polymers offer tunable properties based on metal-ligand interactions.
- Spin crossover materials exhibit distinct magnetic states, crucial for data storage and sensing.
- The synthesis of complex, interpenetrated frameworks remains a challenge in materials chemistry.
Purpose of the Study:
- To synthesize and characterize a novel 2-D coordination polymer based on Fe(II) and [Au(CN)2]-.
- To investigate the structural transformation of the 2-D polymer into 3-D coordination open frameworks.
- To explore the reversibility of this transformation and its impact on spin crossover behavior.
Main Methods:
- Polymer synthesis using iron(II) salts and potassium gold cyanide.
- X-ray crystallography for detailed structural analysis of the 2-D and 3-D frameworks.
- Variable-temperature magnetic susceptibility measurements to probe spin crossover properties.
Main Results:
- Successful synthesis of a 2-D grid polymer composed of Fe(II) ions bridged by [Au(CN)2]-.
- Observation of a reversible crystal-to-crystal transformation into a system of three interpenetrated 3-D coordination open frameworks with NbO topology.
- Demonstration of spin crossover behavior in both the 2-D and 3-D forms, with reversibility linked to the structural transformation.
Conclusions:
- A novel 2-D coordination polymer can be controllably transformed into complex, interpenetrated 3-D frameworks.
- The observed crystal-to-crystal transformation is reversible and influences the spin crossover properties.
- This work demonstrates a pathway for designing responsive materials with potential applications in sensing and molecular switches.
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