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Published on: July 19, 2019
Four-coordinate iron(II) porphyrinates: electronic configuration change by intermolecular interaction
Chuanjiang Hu1, Bruce C Noll, Charles E Schulz
1Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA.
Inorganic Chemistry
|January 30, 2007
Summary
Researchers synthesized and studied three iron(II) porphyrinate complexes. A new crystalline phase of iron(II) tetraphenylporphyrin (Fe(TPP)) exhibits a saddled core and distinct electronic properties due to intermolecular interactions.
Area of Science:
- Coordination Chemistry
- Materials Science
- Solid-State Chemistry
Background:
- Iron(II) porphyrinates are crucial in various chemical and biological processes.
- Understanding the structural and electronic properties of these complexes is key to their application.
- Polymorphism in metal-organic complexes can significantly alter their properties.
Purpose of the Study:
- To synthesize and characterize novel four-coordinate iron(II) tetraarylporphyrinates.
- To investigate the structural differences between different crystalline phases of iron(II) tetraphenylporphyrin (Fe(TPP)).
- To explore the impact of intermolecular interactions on the electronic structure of Fe(TPP) phases.
Main Methods:
- Synthesis of three iron(II) tetraarylporphyrin derivatives.
- X-ray crystallography to determine the solid-state structures.
- Mössbauer spectroscopy and magnetic susceptibility measurements for electronic characterization.
Main Results:
- Three four-coordinate iron(II) porphyrinates were successfully synthesized.
- A new crystalline phase of Fe(TPP) was identified, distinct from a previously reported phase.
- The new Fe(TPP) phase features a highly saddled porphyrin core and exhibits unique electronic properties evidenced by spectroscopic and magnetic data, attributed to intermolecular interactions.
Conclusions:
- The existence of distinct crystalline phases for Fe(TPP) with different porphyrin core conformations and electronic structures has been confirmed.
- Intermolecular interactions play a significant role in dictating the electronic properties of Fe(TPP) in the solid state.
- This study highlights the importance of considering polymorphism in the design and application of iron porphyrinate complexes.
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