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Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
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Comparison of through-space homonuclear correlations between quadrupolar nuclei in solids
Jennifer S Gómez1, Julien Trébosc2, Nghia Tuan Duong3
1Univ. Lille, CNRS, Centrale Lille, Univ. Artois, UMR 8181 - UCCS - Unité de Catalyse et Chimie du Solide, Lille 59000, France.
Journal of Magnetic Resonance (San Diego, Calif. : 1997)
|February 25, 2023
Summary
This study compares two-dimensional double-quantum to single-quantum (DQ-SQ) and single-quantum to single-quantum (SQ-SQ) homonuclear correlation experiments for solid-state quadrupolar nuclei. DQ-SQ correlations are recommended for probing proximities between nuclei with similar frequencies.
Area of Science:
- Solid-state Nuclear Magnetic Resonance (NMR) spectroscopy.
- Quantum coherence manipulation in magnetic resonance.
Background:
- Homonuclear correlation experiments are crucial for identifying proximities between identical quadrupolar nuclei in solids.
- Existing methods utilize either single-quantum (SQ) or double-quantum (DQ) coherences during the indirect evolution period (t1).
Purpose of the Study:
- To compare the efficiency and robustness of 2D DQ-SQ and SQ-SQ homonuclear correlation experiments.
- To evaluate these methods for half-integer spin quadrupolar nuclei (11B, I=3/2 and 27Al, I=5/2) with small chemical shift anisotropy (CSA).
Main Methods:
- Experimental comparison of DQ-SQ and SQ-SQ techniques on model samples: Li2B4O7 for 11B and AlPO4-14 for 27Al.
- Application of specific recoupling schemes: [SR221] or [BR221] bracketed DQ-SQ for 11B, and BR221 un-bracketed DQ-SQ for 27Al.
Main Results:
- DQ-SQ homonuclear correlations are recommended for both 11B and 27Al isotopes.
- These methods effectively probe proximities between nuclei with close or identical frequencies.
- Specific recoupling schemes are recommended based on the isotropic chemical shift differences.
Conclusions:
- 2D DQ-SQ homonuclear correlation experiments offer superior performance for studying nuclear proximities in solids.
- The choice of recoupling scheme within DQ-SQ depends on the specific isotopic properties and chemical shift differences.
Keywords:
Double-quantum coherencesHomonuclear correlationQuadrupolar nucleiSingle-quantum coherencesSpatial proximityMore Related Videos
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