Multiple-quantum magic-angle spinning applications

While the main recent advance in NMR has been the development of multidimensional spectroscopy, novel catalytic applications include in situ studies and two-dimensional (2D) solid-state techniques such as correlation spectroscopy, spin diffusion, and quadrupole nutation. Completely new techniques have appeared, such as multiple-quantum spin counting, and old ones have developed in quite unexpected directions. For example, cross-polarization, a 20-year-old experiment, has recently been applied to quadmpolar nuclei to yield important new information on heterogeneous catalysts. Magic-angle spinning (MAS) of quadru-polar nuclei has been extended to methods in which the sample is spun about two different angles either simultaneously or sequentially (DOR and DAS). These experiments have been made possible by the significant advances in NMR instrumentation in the last decade. 

C. Filip, M. Bertmer, D.E. Demco, B. Bliimich, Application of the Floquet theory to multiple quantum NMR of dipolar-coupled multi-spin systems under magic angle spinning. Mol. Phys. 99 (2001) 1575. 

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