Frequency offset refocused PISEMA-type sequences.

Sergey V Dvinskikh; Dick Sandström

doi:10.1016/j.jmr.2005.03.016

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Frequency offset refocused PISEMA-type sequences.

Sergey V Dvinskikh·Dick Sandström

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Abstract

The popular PISEMA experiment is highly sensitive to the 1H chemical shift dispersion and the choice of the 1H carrier frequency. This is due to the off-resonance 1H irradiation in the FSLG-CP sequence employed during the dipolar evolution period. In the modified approach described in this work, the interfering frequency offset terms are suppressed. In the new pulse schemes, conventional FSLG-CP is intercalated with 180 degrees pulses applied simultaneously to both frequency channels, and with phases set orthogonal to those of the spin-lock fields. The technique is demonstrated on a nematic liquid-crystalline sample. Extensions to amplitude-modulated FSLG-CP recoupling under MAS are also presented.

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Algorithms Computer Simulation Models, Chemical Nuclear Magnetic Resonance, Biomolecular Signal Processing, Computer-Assisted Comparative Study Evaluation Study Journal Article Research Support, Non-U.S. Gov't

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Sergey V Dvinskikh, Dick Sandström. 2005-04-22. Frequency offset refocused PISEMA-type sequences.. https://doi.org/10.1016/j.jmr.2005.03.016

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