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Measuring the Spin-Lattice Relaxation Magnetic Field Dependence of Hyperpolarized [1-13C]pyruvate
Published on: September 13, 2019
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Slow magnetic relaxation in 8-coordinate Mn(II) compounds
Li-Xin Wang1,2, Xiao-Fan Wu3, Xin-Xin Jin3
1Key Laboratory of Optoelectronic Chemical Materials and Devices (Ministry of Education), School of Optoelectronic Materials and Technology, Jianghan University, Wuhan, 430056, China. xiangjing@yangtzeu.edu.cn.
Dalton Transactions (Cambridge, England : 2003)
|October 9, 2023
Summary
This study introduces four novel manganese(II) compounds exhibiting slow magnetic relaxation. These single-molecule magnets (SMMs) demonstrate potential despite small negative D values, expanding the field of high-spin Mn(II) SMMs.
Area of Science:
- Coordination Chemistry
- Materials Science
- Magnetism
Background:
- Development of high-spin manganese(II)-based single-molecule magnets (SMMs) lags behind other first-row transition metals.
- Previous success in designing Fe(II), Co(II), and Fe(III) SMMs with a coordination number of 8 inspired this work.
Purpose of the Study:
- To design and synthesize novel Mn(II) analogues with a high coordination number of 8.
- To investigate the magnetic properties and slow magnetic relaxation behaviors of these new Mn(II) compounds.
Main Methods:
- Synthesis of four Mn(II) compounds using tetradentate ligands (L1-L4) and hydrated Mn(II) perchlorate.
- Crystal structure determination via X-ray crystallography to confirm coordination number.
- Magnetic property investigations, including analysis of slow magnetic relaxation under a direct current field.
Main Results:
- Four new Mn(II) compounds, [MnII(Ln)2](ClO4)2 (1-4), were successfully synthesized.
- X-ray crystallography confirmed an oversaturated coordination number of 8 for the Mn(II) centers in all compounds.
- All synthesized Mn(II) compounds exhibited slow magnetic relaxation behavior, even with small negative D values.
Conclusions:
- The strategy of designing high coordination number complexes is effective for developing Mn(II)-based SMMs.
- The synthesized Mn(II) compounds display promising slow magnetic relaxation, contributing to the advancement of Mn(II) SMM research.
- Further exploration of Mn(II) complexes with high coordination numbers is warranted for discovering new SMMs.
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