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Updated: May 30, 2026
06:53
Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
Single-molecule magnet behaviour in a tetrathiafulvalene-based electroactive antiferromagnetically coupled dinuclear
Fabrice Pointillart1, Yann Le Gal, Stéphane Golhen
1Sciences Chimiques de Rennes, UMR 6226 CNRS, Université de Rennes 1, 263 Avenue du Général Leclerc, 35042 Rennes Cedex, France.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|August 6, 2011
Summary
This study synthesizes novel dinuclear lanthanide complexes. These complexes exhibit antiferromagnetic interactions and slow magnetization relaxation, paving the way for molecular magnetism research.
Area of Science:
- Coordination Chemistry
- Materials Science
- Magnetochemistry
Background:
- Lanthanide complexes are crucial in developing single-molecule magnets.
- Designing dinuclear lanthanide complexes with specific bridging ligands is key to controlling magnetic properties.
Purpose of the Study:
- To synthesize and characterize novel dinuclear lanthanide complexes using specific precursors and ligands.
- To investigate the magnetic exchange interactions and relaxation dynamics in these dinuclear complexes.
Main Methods:
- Synthesis of dinuclear lanthanide complexes [{Ln(tta)(3)(L(1))}(2)]·xCH(2)Cl(2) (Ln=Dy(III), Gd(III)).
- X-ray crystallography to determine the crystal structure and coordination environment.
- Magnetic susceptibility measurements (DC and AC) to study magnetic interactions and relaxation.
- Analysis using empirical methods and the Ising model for Dy(III) and isotropic Gd(III) derivatives.
Main Results:
- Dinuclear complexes with bridging nitroxide groups were successfully synthesized.
- Antiferromagnetic exchange interactions were confirmed for both Dy(III) (J = -2.30 cm(-1)) and Gd(III) (J = -0.031 cm(-1)) complexes.
- The Dy(III) complex (1) exhibits slow magnetization relaxation, with an energy barrier of 87(1) K and pre-exponential factor of 5.48(4)×10(-7) s.
- Applied external magnetic fields can alter the magnetic interactions and induce quantum tunneling.
Conclusions:
- The synthesized dinuclear lanthanide complexes are promising candidates for molecular magnetism.
- The study provides insights into the relationship between structure, magnetic interactions, and relaxation dynamics in lanthanide complexes.
- These findings contribute to the development of new magnetic materials with potential applications in data storage and quantum computing.
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