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Thermochemical Studies of Ni(II) and Zn(II) Ternary Complexes Using Ion Mobility-Mass Spectrometry
Published on: June 8, 2022
Mixed bridged dinuclear Ni(II) complexes: synthesis, structure, magnetic properties and DFT study
Atanu Banerjee1, Reena Singh, Deepak Chopra
1Inorganic Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata, 700 032, India.
Dalton Transactions (Cambridge, England : 2003)
|November 26, 2008
Summary
Synthesized nickel(II) complexes exhibit distinct magnetic interactions, with phenoxo bridges mediating antiferromagnetism and azido/chloro groups facilitating ferromagnetism. Computational analysis confirms these findings, revealing competitive interactions influencing overall magnetic behavior.
Area of Science:
- Coordination Chemistry
- Inorganic Chemistry
- Materials Science
Background:
- Nickel(II) complexes with specific ligand structures are of interest for their magnetic properties.
- Understanding bridging ligand effects on magnetic exchange is crucial for designing functional materials.
Purpose of the Study:
- To synthesize and characterize novel dinuclear nickel(II) complexes.
- To investigate the magnetic interactions and electronic properties of these complexes.
- To elucidate the role of bridging ligands (phenoxo, chloro, azido) in mediating magnetic exchange.
Main Methods:
- Synthesis of dinuclear nickel(II) complexes using a specific Schiff base ligand.
- X-ray crystallography to determine the coordination geometry of nickel(II) centers.
- Electrochemical studies to analyze redox properties.
- Magnetic susceptibility measurements to probe magnetic interactions.
- Broken symmetry density functional theory (DFT) calculations to determine exchange coupling constants (J) and interaction pathways.
Main Results:
- Two green-colored dinuclear nickel(II) complexes, [Ni2(L)(Cl)(H2O)] and [Ni2(L)(N3)(H2O)], were successfully synthesized.
- One nickel(II) center adopts a distorted square pyramidal geometry, while the other exhibits a distorted octahedral geometry.
- Complexes display one-electron anodic responses around 0.70 V and 1.10 V.
- Complex 1 shows weak antiferromagnetic coupling, while Complex 2 exhibits weak ferromagnetic coupling.
- DFT calculations confirm experimental magnetic data and identify phenoxo bridges for antiferromagnetism and azido/chloro groups for ferromagnetism.
Conclusions:
- The synthesized nickel(II) complexes exhibit tunable magnetic properties influenced by bridging ligands.
- Phenoxo bridges favor antiferromagnetic coupling, whereas azido and chloro bridges promote ferromagnetic coupling.
- Competitive magnetic interactions within the complexes modulate the overall magnetic behavior, offering insights for molecular magnetism design.
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