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Updated: Apr 26, 2026
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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
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Thermal- and light-induced spin-crossover bistability in a disrupted Hofmann-type 3D framework
Natasha F Sciortino1, Suzanne M Neville, Jean-François Létard
1School of Chemistry, The University of Sydney , Sydney, New South Wales 2006, Australia.
Inorganic Chemistry
|July 22, 2014
Summary
This study explores a novel iron coordination compound with a bent ligand, revealing an unusual structure that leads to distinct magnetic properties and a light-induced spin transition. The material exhibits hysteretic spin switching and photomagnetism.
Area of Science:
- Coordination Chemistry
- Materials Science
- Magnetism
Background:
- The synthesis and topological characterization of 3D and 2D coordination polymers based on linear ligands and [Fe(II)M(II)(CN)4] (M(II) = Pt, Pd, Ni) are well-established.
- Hofmann-type coordination networks are known for their diverse structural motifs and potential applications in magnetism and gas storage.
Purpose of the Study:
- To investigate the structural and magnetic consequences of incorporating a bent bispyridyl ligand, 4,4'-dipyridylselenide (DPSe), into a [Fe(II)Pt(II)(CN)4] framework.
- To characterize the spin transition behavior and photomagnetic properties of the resulting coordination polymer, [Fe(H2O)2Fe(DPSe)2(Pt(CN)4)2]·3EtOH.
Main Methods:
- Single-crystal X-ray diffraction for structural analysis.
- Magnetic susceptibility measurements to probe spin transitions.
- Variable-temperature UV-Vis spectroscopy to investigate photomagnetic effects.
Main Results:
- The synthesized material exhibits an unusual 3D topology, deviating from typical Hofmann structures, with two distinct iron(II) environments ([Fe(II)N6] and [Fe(II)N4O2]).
- A complete and abrupt hysteretic spin transition was observed for the [Fe(II)N6] site (Fe1) between 120 K and 130 K, while the [Fe(II)N4O2] site (Fe2) remained high-spin.
- The material demonstrated a light-induced excited spin-state trapping (LIESST) effect with bistability, evidenced by a hysteresis loop between 60 K and 66 K.
Conclusions:
- The bent DPSe ligand and axial water coordination lead to a unique coordination polymer structure with distinct magnetic properties.
- The observed spin transition and photomagnetic behavior highlight the potential of this material for applications in molecular switches and memory devices.
- This work expands the understanding of structure-property relationships in coordination polymers, particularly those exhibiting spin crossover and LIESST phenomena.
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