Analytical Instrument Documents

rss

JEOL Resources

Documentation in support of your JEOL product.

Proton triple-quantum solid-state NMR spectroscopy at slow MAS ∼10 kHz

Highlights

  • New second-order TQ recoupling sequence has been designed based on RNνn symmetry sequences at slow MAS.
  • The new (R1816R181−6)31 sequence show a factor of 6 higher TQ excitation efficiency that previous approaches.
  • The TQ dimension is free of spinning sidebands due to the absence of gamma-angle dependence of the recoupled Hamiltonian

Abstract

Solid-state NMR is a valuable tool for elucidating the structures and dynamics of materials at an atomic level. Proton multiple-quantum (MQ) /single-quantum (SQ) correlation NMR spectroscopy is widely used to probe spatial proximity among protons. In the triple-quantum (TQ)/SQ correlation experiment, the excitation of triple-quantum (TQ) coherences is traditionally achieved by a 90° pulse in conjugation with double-quantum (DQ) recoupling sequences. Nevertheless, such sequences often suffer from low TQ filtering efficiency and may lead to overlapping spinning sidebands in the indirect TQ dimension, especially at a slow MAS frequency. Herein, we design several supercycled symmetry-based RNnν γ-free TQ recoupling sequences and compare their performance via extensive numerical simulation and experiments. Experimental results further confirm that (R1816R181−6)31 pulse sequence gives the highest TQ filtering efficiency of around 20% in the slow MAS regime (∼10 kHz). The 2D TQ/SQ spectrum at slow MAS is completely free of spinning sidebands in the TQ dimension due to its γ-free nature. We establish that such a γ-free (R1816R181−6)31  pulse sequence is a superior candidate for TQ spectroscopy at slow MAS frequency.

Click Link to View Article: https://doi.org/10.1016/j.jmro.2021.100020

Showing 0 Comment



Comments are closed.

Other Resources

The following resources are available for the JEOL Analytical Instruments:

Media

Corona - Glow Discharge (DART Ion Source)

February 22, 2020
2156