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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Four-site cooperative spin crossover in a mononuclear Fe(II) complex
Anders Lennartson1, Andrew D Bond, Stergios Piligkos
1Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense, Denmark.
Angewandte Chemie (International Ed. in English)
|October 2, 2012
Summary
Researchers characterized a mononuclear iron(II) complex with an N(4)S(2) coordination set. Two forms showed cooperative spin crossover (SCO), a rare behavior for sulfur-containing compounds, warranting further study.
Area of Science:
- Inorganic Chemistry
- Materials Science
- Solid-State Chemistry
Background:
- Spin crossover (SCO) is a phenomenon in transition metal complexes where a change in spin state can be triggered by external stimuli.
- Iron(II) complexes are widely studied for SCO properties, but the inclusion of sulfur donor atoms is less common.
Purpose of the Study:
- To characterize a mononuclear iron(II) complex with an N(4)S(2) coordination environment.
- To investigate the spin crossover behavior of this complex in different polymorphic forms.
Main Methods:
- Crystallographic analysis to determine the structure of four polymorphic forms.
- Analysis of the crystal structure to identify a fully ordered 1:3 high-spin/low-spin state.
Main Results:
- Characterization of a mononuclear iron(II) complex featuring an N(4)S(2) coordination set.
- Discovery of cooperative spin crossover (SCO) in two of the four polymorphic forms.
- Confirmation of SCO via crystal structure of an ordered high-spin/low-spin state.
Conclusions:
- The presence of sulfur donor atoms in SCO-active compounds is unusual and significant.
- Further investigation into iron(II) complexes with sulfur ligands for SCO applications is recommended.
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