A Bis(μ-oxido)dinickel(III) Complex with a Triplet Ground State

Area of Science:

• Inorganic Chemistry
• Materials Science
• Quantum Chemistry

Background:

• High-valent metal complexes with dinuclear cores are crucial in catalysis.
• Understanding magnetic coupling in such systems is key to designing new materials.
• The [M2(μ-O)2] diamond core is common, but high-valent states are less explored.

Purpose of the Study:

• To synthesize and characterize a novel bis(μ-oxido)dinickel(III) complex.
• To investigate the magnetic properties and electronic structure of the dinickel(III) complex.
• To explore the reactivity of the complex in oxidation and hydrogen abstraction reactions.

Main Methods:

• Single crystal X-ray diffraction for structural determination.
• Resonance Raman and ESI-mass spectrometry for characterization.
• SQUID magnetometry and EPR spectroscopy for magnetic studies.
• Density Functional Theory (DFT) for electronic structure and coupling analysis.

Main Results:

• Successful synthesis and full characterization of the bis(μ-oxido)dinickel(III) complex.
• Experimental and computational evidence for a triplet ground state and ferromagnetic coupling between Ni(III) centers.
• Unprecedented observation of a triplet ground state for a [M2(μ-O)2] diamond core in a high-valent metal complex.
• Demonstrated reactivity in hydrogen abstraction and oxygenation of substrates.

Conclusions:

• The dinickel(III) complex represents a new class of high-valent metal compounds.
• The observed triplet ground state and ferromagnetic coupling offer insights into electronic structures of dinuclear complexes.
• The complex's reactivity suggests potential applications in oxidation catalysis.