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Published on: August 12, 2019
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Angle-dependent spin crossover properties in polymorphic iron(II) complexes based on pyridine-triazole derivatives.
Emmelyne Cuza1, Nicolas Delsuc2, Jerôme Marrot3
1Institut des Matériaux Poreux de Paris, UMR 8004 CNRS, Ecole Normale Supérieure, Ecole Supérieure de Physique et de Chimie Industrielles de Paris, PSL University, 75005 Paris, France. antoine.tissot@ens.psl.eu.
Dalton Transactions (Cambridge, England : 2003)
|March 25, 2025
Summary
Two new iron(II) compounds exhibiting distinct magnetic behaviors were synthesized. Their crystalline packing significantly impacts spin crossover properties, crucial for molecular switches.
Area of Science:
- Coordination Chemistry
- Materials Science
- Solid-State Chemistry
Background:
- Spin crossover (SCO) in iron(II) complexes is sensitive to the molecular environment.
- Polymorphism can significantly alter the physical properties of coordination compounds.
Purpose of the Study:
- Synthesize and characterize new iron(II) compounds with pyridine-triazole ligands.
- Investigate the influence of crystalline packing on spin crossover properties.
- Compare thermodynamic and kinetic products regarding their magnetic behavior.
Main Methods:
- Synthesis of two new Fe(II) compounds.
- Single crystal X-ray diffraction for structural analysis.
- Magnetic susceptibility measurements over a temperature range.
Main Results:
- Two polymorphs of iron(II) compounds with a pyridine-triazole ligand and NCS- co-ligand were identified.
- Compound 1 exhibits sharp spin crossover behavior.
- Compound 2 remains in a high-spin state across the measured temperature range.
Conclusions:
- Crystalline packing plays a critical role in modulating the spin crossover properties of Fe(II) complexes.
- Thermodynamic and kinetic control during synthesis can lead to distinct SCO behaviors in polymorphs.
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