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Iron(II) Spin Crossover Complexes with 4,4'-Dipyridylethyne-Crystal Structures and Spin Crossover with Hysteresis
Katja Dankhoff1, Charles Lochenie1, Birgit Weber1
1Department of Chemistry, Inorganic Chemistry IV, University of Bayreuth, Universitätsstr. 30, 95447 Bayreuth, Germany.
Abstract:
Three new iron(II) 1D coordination polymers with cooperative spin crossover behavior showing thermal hysteresis loops were synthesized using N2O2 Schiff base-like equatorial ligands and 4,4'-dipyridylethyne as a bridging, rigid axial linker. One of those iron(II) 1D coordination polymers showed a 73 K wide hysteresis below room temperature, which, upon solvent loss, decreased to a still remarkable 30 K wide hysteresis. Single crystal X-ray structures of two iron(II) coordination polymers and T-dependent powder XRD patterns are discussed to obtain insight into the structure property relationship of those materials.
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