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Updated: May 31, 2026

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Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
Published on: October 18, 2019
Tris(η-cyclo-penta-dien-yl)hafnium(III)
Summary
The crystal structure reveals a hafnium(III) atom bonded to three cyclopentadienyl ligands in a trigonal-planar arrangement. This unique molecular geometry is centered on a sixfold inversion axis.
Area of Science:
- Organometallic Chemistry
- Inorganic Chemistry
- Crystallography
Background:
- Organometallic compounds containing early transition metals are crucial in catalysis and materials science.
- Understanding the coordination chemistry of hafnium is essential for developing new applications.
- The synthesis and structural characterization of novel hafnium complexes provide fundamental insights into metal-ligand bonding.
Purpose of the Study:
- To determine the precise crystal structure of the title compound, tris(cyclopentadienyl)hafnium(III).
- To elucidate the coordination geometry and bonding environment around the hafnium(III) center.
- To investigate the molecular symmetry and packing in the solid state.
Main Methods:
- Single-crystal X-ray diffraction was employed to collect diffraction data.
- The crystal structure was solved and refined using established crystallographic software.
- Analysis of bond lengths, bond angles, and symmetry elements provided structural details.
Main Results:
- The crystal structure of [Hf(C5H5)3] was successfully determined.
- Three cyclopentadienyl ligands coordinate to the hafnium(III) atom.
- The complex adopts a trigonal-planar geometry around the hafnium center, lying on a sixfold inversion axis.
Conclusions:
- The trigonal-planar coordination geometry around Hf(III) in [Hf(C5H5)3] is confirmed.
- The molecule exhibits high symmetry, residing on a sixfold inversion axis.
- This structural characterization contributes to the understanding of organohafnium compounds.
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