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Reversible core-interconversion of an iron(III) dihydroxo bridged complex
Athanassios K Boudalis1, Juan Modesto Clemente-Juan, Françoise Dahan
1Institute of Materials Science, NCSR "Demokritos", 153 10 Aghia Paraskevi Attikis, Greece. tbou@ims.demokritos.gr
Inorganic Chemistry
|October 22, 2008
Summary
Two novel iron complexes featuring 2-(2'-hydroxyphenyl benzimidazole) (Hhbi) were synthesized. One complex shows paramagnetic relaxation and zero-field splitting, while the other undergoes reversible core conversion upon drying.
Area of Science:
- Inorganic Chemistry
- Coordination Chemistry
- Materials Science
Background:
- Iron complexes with benzimidazole ligands are of interest for their diverse magnetic and structural properties.
- Understanding the behavior of these complexes under different conditions is crucial for potential applications.
Purpose of the Study:
- To synthesize and characterize novel iron complexes with the 2-(2 ahydroxyphenyl benzimidazole) ligand.
- To investigate the magnetic properties and structural transformations of these iron complexes.
Main Methods:
- X-ray crystallography for structural determination.
- Mossbauer spectroscopy and X-band electron paramagnetic resonance (EPR) spectroscopy for magnetic characterization.
- Magnetic susceptibility measurements and mass spectrometry for analyzing complex behavior.
Main Results:
- Two iron complexes, [Fe(Hhbi)(2)(NO3)].2EtOH and [Fe2(mu-OH)2(Hhbi)4].2H2O.8EtOH, were successfully synthesized and crystallized.
- Complex 1 exhibited paramagnetic relaxation and significant zero-field splitting with rhombic distortion.
- Complex 2 showed a reversible core conversion to an oxo-bridged diferric species upon drying, with partial decomposition.
Conclusions:
- The study details the synthesis and characterization of two unique iron complexes.
- The findings highlight the distinct magnetic properties of the mononuclear complex and the reversible structural transformation of the dinuclear complex.
- These results contribute to the understanding of iron-ligand interactions and their influence on complex stability and properties.
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