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Solid-state ¹⁷O NMR spectroscopy of paramagnetic coordination compounds
Xianqi Kong1, Victor V Terskikh, Rahul L Khade
1Department of Chemistry, Queen's University, Kingston, Ontario, K7L 3N6 (Canada).
Angewandte Chemie (International Ed. in English)
|February 20, 2015
Summary
This study demonstrates high-quality solid-state oxygen-17 NMR for paramagnetic coordination compounds. These paramagnetic shifts offer insights into metal-ligand interactions in V(III), Cu(II), and Mn(III) complexes.
Area of Science:
- Inorganic Chemistry
- Solid-State NMR Spectroscopy
- Quantum Chemistry
Background:
- Paramagnetic coordination compounds present challenges for NMR analysis.
- Oxygen-17 (I=5/2) NMR is crucial for understanding metal-oxygen bonding.
- Previous methods lacked resolution for paramagnetic systems.
Purpose of the Study:
- To obtain high-quality solid-state oxygen-17 NMR spectra for paramagnetic coordination compounds.
- To investigate oxygen-17 isotropic paramagnetic shifts in V(III), Cu(II), and Mn(III) complexes.
- To correlate experimental NMR data with quantum-chemical calculations.
Main Methods:
- Solid-state oxygen-17 NMR spectroscopy.
- High magnetic field (21.1 T) and fast magic-angle spinning (MAS).
- Density functional theory (DFT) calculations for hyperfine shift tensors.
Main Results:
- Successful acquisition of high-quality solid-state (17)O NMR spectra.
- Observed (17)O isotropic paramagnetic shifts exceeding 10,000 ppm.
- Qualitative agreement between experimental shifts and DFT-computed hyperfine shift tensors.
Conclusions:
- Solid-state (17)O NMR is a viable technique for studying paramagnetic coordination compounds.
- The observed shifts provide valuable information on electronic structures.
- DFT calculations can aid in interpreting experimental (17)O NMR data.
Keywords:
17O NMR spectroscopycoordination complexesdensity functional calculationshyperfine interactionsparamagnetismMore Related Videos
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