Advances in STMAS

Ashbrook, S.E. and Wimperiss, S. (2008) Advances in STMAS. In: Harris, R.K. and Waylishen, R. (eds.) Encyclopedia of Magnetic Resonance. Wiley: Chichester, UK. ISBN 9780470034590 (doi: 10.1002/9780470034590.emrstm1032)

Abstract

The satellite transition magic angle spinning (STMAS) experiment is a method of obtaining high-resolution NMR spectra of half-integer spin quadrupolar nuclei, such as ¹⁷O, ²³Na, and ²⁷Al, in solids. In this article, we review the major developments of the original experiment that have taken place since its introduction by Gan in 2000 (see Satellite Transition NMR Spectroscopy of Half-Integer Quadrupolar Nuclei under Magic-Angle Spinning). After a brief resume of how the basic experiment is performed, we discuss a method for removing the autocorrelation “diagonal” from the two-dimensional spectrum (DQF-STMAS), a version of the technique that self-compensates for deviation of the rotor axis from the magic angle (SCAM-STMAS), and an “ultrafast” STMAS experiment that allows a high-resolution spin I = 3/2 spectrum to be acquired in a single transient (STARTMAS). Next, we describe the unique sensitivity of the STMAS experiment to molecular-scale dynamics on the microsecond timescale and to third-order quadrupolar and second-order “cross-term” interactions involving the quadrupolar and dipolar or shielding interactions. Finally, we discuss the signal-to-noise advantage of STMAS (compared with the rival MQMAS method) and how this makes it particularly suitable for studying low-γ nuclei, such as 25Mg and 39K, and materials that can only be obtained in small quantities.

• Item Type: Book Sections
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Wimperis, Professor Stephen
• Authors: Ashbrook, S.E., and Wimperiss, S.
• Subjects: Q Science > QC Physics
• College/School: College of Science and Engineering > School of Chemistry
• Publisher: Wiley
• ISBN: 9780470034590