Improving solid-state NMR dipolar recoupling by optimal control.

Cindie T Kehlet; Astrid C Sivertsen; Morten Bjerring; Timo O Reiss; Navin Khaneja; Steffen J Glaser; Niels Chr Nielsen

doi:10.1021/ja048786e

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Improving solid-state NMR dipolar recoupling by optimal control.

Cindie T Kehlet·Astrid C Sivertsen·Morten Bjerring·Timo O Reiss·Navin Khaneja·Steffen J Glaser·Niels Chr Nielsen

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Abstract

We present the first solid-state NMR experiments developed using optimal control theory. Taking heteronuclear dipolar recoupling in magic-angle-spinning NMR as an example, it proves possible to significantly improve the efficiency of the experiments while introducing robustness toward instrumental imperfections such as radio frequency inhomogeneity. The improvements are demonstrated by numerical simulations as well as practical experiments on a 13Calpha,15N-labeled powder of glycine. The experiments demonstrate a gain of 53% in the efficiency for 15N to 13Calpha coherence transfer relative to the typically double-cross-polarization experiments.

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Carbon Isotopes Glycine Nitrogen Isotopes Nuclear Magnetic Resonance, Biomolecular Journal Article Research Support, Non-U.S. Gov't

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Cindie T Kehlet, Astrid C Sivertsen, Morten Bjerring, Timo O Reiss, Navin Khaneja, Steffen J Glaser, Niels Chr Nielsen. 2004-08-25. Improving solid-state NMR dipolar recoupling by optimal control.. https://doi.org/10.1021/ja048786e

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