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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.
Abstract:
Two new Fe(II) compounds based on a pyridine-triazole ligand with an NCS- co-ligand were synthesized as thermodynamic (1) and kinetic (2) products. Single crystal X-ray diffraction evidenced that these compounds are polymorphs. The magnetic susceptibility of each compound was recorded, which showed that 1 undergoes a sharp spin crossover, while 2 remains in the high spin state across the temperature range. We discussed here the importance and impact of crystalline packing on the switching properties of these compounds.
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