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A water sensitive ferromagnetic [Ni(cyclam)]2[Nb(CN)8] network.
Beata Nowicka1, Maria Bałanda, Mateusz Reczyński
1Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Kraków, Poland. beata.nowicka@uj.edu.pl
Dalton Transactions (Cambridge, England : 2003)
|December 11, 2012
Summary
A novel 3D diamond-like network was synthesized from nickel(II) cyclam and tungsten(IV) octacyanide. A related niobium(IV) compound exhibits magnetic ordering, but its properties are sensitive to hydration and dehydration cycles.
Area of Science:
- Coordination Chemistry
- Materials Science
- Solid-State Chemistry
Background:
- Metal-organic frameworks (MOFs) and coordination polymers are synthesized using metal ions and organic ligands.
- The properties of these materials are highly dependent on their structural characteristics and composition.
Purpose of the Study:
- To synthesize and characterize novel 3D coordination networks.
- To investigate the magnetic properties of a niobium-based coordination compound.
- To explore the effects of dehydration and rehydration on the structural and magnetic properties.
Main Methods:
- Single-crystal X-ray diffraction for structural analysis.
- Magnetic susceptibility measurements (DC and AC) to probe magnetic ordering.
- Thermogravimetric analysis to study dehydration behavior.
Main Results:
- A 3D diamond-like network, [Ni(cyclam)2][W(CN)8]·3.5H2O, was successfully synthesized and characterized.
- An analogous niobium compound, [Ni(cyclam)2][Nb(CN)8]·3.5H2O, was obtained as a powder and exhibits long-range magnetic ordering (Tc = 11.8 K) and magnetic hysteresis.
- Dehydration/rehydration cycles significantly alter the structure and magnetic properties, suggesting the formation of multiphase systems and partial reversibility.
Conclusions:
- The study demonstrates the successful synthesis of a novel 3D coordination network with potential applications in materials science.
- The niobium-based compound showcases interesting magnetic properties that are tunable through environmental changes (hydration).
- The observed structural and magnetic changes highlight the sensitivity of these coordination materials to external stimuli.
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