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Updated: Jul 18, 2026

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Adiabatic 1H decoupling scheme for very accurate intensity measurements in 13C NMR
1LAIEM-CNRS UMR 6006, Faculté des Sciences et Techniques-Université de NANTES, 2 rue de la Houssinière-BP 92208, 44322 NANTES cedex 3, France.
Abstract:
Adiabatic proton decoupling has been optimized in order to obtain accurate quantitative measurements of intensities on 13C NMR spectra. For each offset, the minimum adiabaticity factor (Km) reached during the pulse was computed. This K(m) profile was used to optimize the peak value and the swept frequency range of the adiabatic pulses. With a cosinus amplitude modulation, offset-independent-adiabaticity, and the M4P5-M4P9-M4P5'-M4P9' phase cycle, an accuracy of 2 per thousand for the 13C NMR measurements was reached. An approach using bi-labeled 13C acetic acid and ethanol at 99% allowed a fine experimental determination of the uniformity of the decoupling profile. The comparison with WALTZ-16 highlights the improvements in the uniformity of the proton decoupling.
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