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Updated: Sep 22, 2025
06:35
Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
8.2K
Supramolecular isomorphic dodecanuclear cobalt clusters with the same metal shell but different core ligands
Xiao-Wen Liang1, Lin-Lin Zhang1, Ting Zhang1
1School of Chemistry and Chemical Engineering, TKL of Organic Solar Cells and Photochemical Conversion, Tianjin University of Technology, Tianjin 300384, China. zhaojp@tjut.edu.cn.
Dalton Transactions (Cambridge, England : 2003)
|May 23, 2022
Summary
Two new dodecanuclear cobalt complexes with identical structures were synthesized. Differences in ligands, specifically the addition of acetate, caused a visible light absorption shift and revealed antiferromagnetic interactions between cobalt ions.
Area of Science:
- Supramolecular Chemistry
- Coordination Chemistry
- Inorganic Chemistry
Background:
- Dodecanuclear metal clusters offer unique structural and magnetic properties.
- Isomorphic complexes provide a platform for studying structure-property relationships.
Purpose of the Study:
- To synthesize and characterize two novel isomorphic dodecanuclear cobalt complexes.
- To investigate the impact of ligand variation on structural and spectroscopic properties.
- To explore the magnetic behavior of the cobalt ions within the clusters.
Main Methods:
- Single-crystal X-ray diffraction for structural determination.
- UV-Vis spectroscopy to analyze electronic transitions.
- Magnetic susceptibility measurements to probe magnetic interactions.
Main Results:
- Two isomorphic dodecanuclear cobalt complexes, [Co12(mtz)3(L)6(NO3)2(OH)(N3)3]·(OH)3 (1) and [Co12(mtz)3(L)6(NO3)2(OH)(N3)(OAc)]·(OH)4 (2), were successfully synthesized.
- Both complexes share the same dodecanuclear core structure composed of two hexanuclear cobalt units, crystallizing in the P- space group.
- The introduction of acetate anions in complex 2 resulted in a blue shift of the visible absorption band.
- Magnetism studies revealed antiferromagnetic interactions between the Co(II) ions in both complexes.
Conclusions:
- The study successfully synthesized and characterized two isomorphic dodecanuclear cobalt complexes.
- Ligand modification, specifically the inclusion of acetate, influences the electronic properties of the complexes.
- Antiferromagnetic coupling is a characteristic feature of the cobalt ions within these dodecanuclear structures.
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