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High-Temperature and High-Pressure In situ Magic Angle Spinning Nuclear Magnetic Resonance Spectroscopy
Published on: October 9, 2020
Solid state NMR at high magic angle spinning frequencies: dipolar chemical shift correlation with adiabatic inversion
Christian Herbst1, Kerstin Riedel, Jörg Leppert
1Molecular Biophysics/NMR spectroscopy group, Leibniz Institute for Age Research, Fritz Lipmann Institute, D-07745, Jena, Germany.
Journal of Biomolecular NMR
|July 26, 2006
Summary
This study demonstrates novel radiofrequency pulse schemes for efficient dipolar recoupling in solid-state NMR. These methods reduce power requirements and improve performance at high spinning speeds.
Area of Science:
- Solid-state Nuclear Magnetic Resonance (NMR) spectroscopy.
- Materials science and structural analysis.
Background:
- Dipolar recoupling is crucial for determining distances in solid-state NMR.
- Conventional methods using rectangular pulses face limitations at high magic angle spinning (MAS) frequencies.
Purpose of the Study:
- To evaluate the efficacy of tanh/tan adiabatic inversion pulse schemes for hetero- and homonuclear dipolar recoupling.
- To present a method for minimizing radiofrequency (RF) power levels in these schemes.
- To demonstrate applicability in challenging spinning speed regimes.
Main Methods:
- Numerical simulations and experimental measurements were employed.
- Optimization of RF pulse sequences considering spinning speed, resonance offsets, H(1) inhomogeneities, and RF field strength.
- Tailoring of frequency and amplitude modulation profiles of inversion pulses.
Main Results:
- The study successfully examined the efficacy of tanh/tan adiabatic inversion pulse schemes.
- An approach to minimize RF power levels was developed and validated.
- The performance of these schemes was shown to be superior to conventional rectangular pulses in certain regimes.
Conclusions:
- Tanh/tan adiabatic inversion pulse schemes offer an effective approach for dipolar recoupling in solid-state NMR.
- These schemes enable efficient recoupling at high MAS frequencies and reduced RF power.
- The developed method provides a valuable tool for structural studies where conventional techniques are insufficient.
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