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Updated: Nov 21, 2025
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Anisotropic exchange interaction and field-induced SMM behaviour in a mixed valence {CoCo} complex
Daiana Cabrosi1, Carlos Cruz2, Verónica Paredes-García2
1Departamento de Química Inorgánica, Analítica y Química Física/INQUIMAE (CONICET), Facultad de Ciencias Exactas y Naturales Universidad de Buenos Aires, Pabellón 2, Ciudad Universitaria, C1428EHA Buenos Aires, Argentina. albores@qi.fcen.uba.ar.
Researchers synthesized a novel hexanuclear cobalt complex with an unprecedented core structure. Magnetic studies revealed field-induced single-molecule magnet behavior at low temperatures, driven by anisotropic exchange interactions.
Area of Science:
- Inorganic Chemistry
- Materials Science
- Magnetochemistry
Background:
- Hexanuclear cobalt complexes are of interest for their magnetic properties.
- Schiff base ligands are versatile in coordinating metal ions.
- Pivalate cobalt precursors offer unique reactivity.
Purpose of the Study:
- To synthesize and structurally characterize a new hexanuclear cobalt(II)/cobalt(III) complex.
- To investigate the magnetic properties and single-molecule magnet behavior of the complex.
- To elucidate the magnetic exchange interactions and relaxation mechanisms.
Main Methods:
- Synthesis utilizing a pivalate cobalt precursor and a Schiff base ligand.
- X-ray crystallography for structural characterization.
- DC and AC magnetic susceptibility measurements.
- Quantum chemical computations.
Main Results:
- Formation of an unprecedented [CoII4CoIII2(μ3-OH)2(μ-OR)2(μ-OR')2(μ-OR'')2]6+ core with an inversion center.
- Identification of two unique Co(ii) sites with unquenched orbital contributions.
- Observation of field-induced single-molecule magnet behavior below 3 K at 1500 Oe.
- Analysis of magnetic data indicating dominant antiferromagnetic exchange and anisotropic interactions.
Conclusions:
- The new hexanuclear cobalt complex exhibits unique structural and magnetic properties.
- Field-induced single-molecule magnet behavior is attributed to relaxation pathways between excited magnetic states.
- Quantum computations support the experimental findings regarding magnetic interactions and mechanisms.
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