Implementing SPAM into STMAS: a net sensitivity improvement in high-resolution NMR of quadrupolar nuclei.
Gan and Kwak recently introduced two new tools for high-resolution 2D NMR methods applied to quadrupolar nuclei: double-quantum filtering in STMAS (DQF-STMAS) and the soft-pulse added mixing (SPAM) idea. Double-quantum filtering suppresses all undesired signals in the STMAS method with limited loss in sensitivity. With SPAM, all pathways are added constructively after the second hard-pulse instead of using a single pathway as previously. Here, the sensitivity, advantages and drawbacks of DQF-STMAS are compared to 3QMAS. Additionally, SPAM can be included into DQF-STMAS method, resulting in a net sensitivity gain with respect to 3QMAS of ca. 10-15.
Amoureux
J P
JP
LCPS, CNRS-8012, ENSCL-USTL, Fr-59652 Villeneuve d'Ascq, France. jean-paul.amoureux@univ-lille1.fr
Delevoye
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Fink
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Taulelle
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Flambard
A
A
Montagne
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