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DOE OSTI · 2522077

Highly Sensitive Measurements of Methylene Dynamics With a Frequency-Selective Double-Quantum Sideband Method

Mayer, Jacob [Ames Laboratory (AMES), Ames, IA (United States); Iowa State University, Ames, IA (United States)]·Perras, Frédéric A. [Ames Laboratory (AMES), Ames, IA (United States); Iowa State University, Ames, IA (United States)] (ORCID:0000000226625119)
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Abstract

Probing the fast dynamics of surface sites using NMR spectroscopy is highly challenging owing to the sites’ high dilution and the difficulties often associated with isotopic enrichment. Intra-CH 2 1 H- 1 H dipolar couplings are ideal probes of motions given that they only involve 1 H’s and the tensor has a well-defined size and orientation. Here, we introduce a frequency-selective variant of the double-quantum sideband method to measure like-spin 1 H- 1 H dipolar coupling constants. The experiment dramatically reduces the instrument time required to measure dynamically-averaged intra-CH 2 dipolar couplings. We demonstrate the performance of the sequence using silica-supported silanes as model highly-mobile surface species.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYDipolar RecouplingDipolar couplingDynamicsFast-MASNuclear magnetic resonance

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Mayer, Jacob [Ames Laboratory (AMES), Ames, IA (United States); Iowa State University, Ames, IA (United States)], Perras, Frédéric A. [Ames Laboratory (AMES), Ames, IA (United States); Iowa State University, Ames, IA (United States)] (ORCID:0000000226625119). 2025-02-21. Highly Sensitive Measurements of Methylene Dynamics With a Frequency-Selective Double-Quantum Sideband Method. https://doi.org/10.1016/j.ssnmr.2025.101994

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