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Updated: Sep 14, 2025
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Ligand-Nuclei Effects on Spin Relaxation in V(IV) Complexes
Roxanna Martinez1, Ökten Üngör1, Cassidy E Jackson2
1Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States.
Inorganic Chemistry
|July 24, 2025
Summary
Magnetic nuclei significantly impact spin relaxation in V(IV) complexes. Ligand nuclear spin identity fine-tunes spin-lattice relaxation, revealing unexpected dependencies on magnetic field and nuclear type.
Area of Science:
- Molecular Magnetism
- Spin Dynamics
- Electron Paramagnetic Resonance (EPR) Spectroscopy
Background:
- Understanding spin relaxation is crucial for developing advanced magnetic materials and molecules.
- The influence of magnetic nuclei on spin relaxation, particularly in ligand shells, requires further investigation.
Purpose of the Study:
- To investigate how different magnetic nuclei in the ligand shell of V(IV) complexes affect spin relaxation.
- To explore the relationship between ligand nuclear spin identity and spin relaxation properties.
Main Methods:
- High-field Electron Paramagnetic Resonance (EPR)
- X-band EPR spectroscopy
- AC magnetic susceptibility measurements
- Raman spectroscopy
Main Results:
- Compound 1 (with 1H ligands) exhibited the longest phase memory relaxation times at high fields, contrary to expectations.
- Spin-lattice relaxation time and its field dependence varied with ligand identity, despite similar electronic structures.
- Unanticipated results highlight the complex interplay between nuclear spins and spin relaxation.
Conclusions:
- Spin-lattice relaxation in these V(IV) complexes is sensitive to the local magnetic environment, which is modulated by the ligand nuclear spin identity.
- Fine-tuning of the ligand shell's nuclear spins offers a pathway to control spin relaxation properties.
- Further research is needed to fully elucidate the mechanisms governing nuclear spin-influenced relaxation.
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