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Updated: Jul 15, 2026

Molecular Entanglement and Electrospinnability of Biopolymers
Published on: September 3, 2014
Modification of spin crossover behavior through solvent assisted formation and solvent inclusion in a triply
Matthias Bartel1, Alina Absmeier, Guy N L Jameson
1Institute of Applied Synthetic Chemistry, Vienna University of Technology, Getreidemarkt 9/163-AC, A-1060 Vienna, Austria.
Abstract:
The 3D coordination polymer [Fe(4ditz)3](PF6)2.solv consists of three interpenetrating infinite networks. There are cavities between iron atoms of different networks, which are partly filled with solvent molecules. With a change of the solvent used during synthesis from methanol to ethanol, the magnetic behavior of the materials changes. Both show an abrupt two-step spin crossover from low spin (S = 0) to high spin (S = 2) with the methanolate curve lying 7 K higher and showing a small hysteresis. Single crystal and powder diffraction studies show that they both have the same structure, but in powder form, the methanolate slowly loses methanol to finally leave about 0.075 MeOH/Fe. In comparison, the bigger ethanol remains at 0.25 EtOH/Fe. These results, in conjunction with thermodynamic data, strongly suggest that the differences in magnetic behavior are largely entropic in nature. Possible reasons for this are discussed.
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