NMR at fast MAS

Over the past 15 years the maximum magic-angle spinning (MAS) frequency has been increasing from 25 kHz to now beyond 100 kHz. Fast rotation of the sample around the magic angle in combination with strong decoupling significantly improves the spectral resolution of heteronuclei of uniformly enriched samples. Because high resolution is a prerequisite for structural investigations of large biological molecules with solid-state NMR, we are interested in the development of methods, which can be used under fast MAS spinning. We must also take into account that the increase in the spinning frequency comes at the price of smaller rotor diameters (from the standard 3.2 mm to 0.8 mm for 100 kHz MAS) and smaller amounts of sample, thus posing spectral sensitivity issues. Moreover, high MAS frequencies also average out very efficiently interactions as the dipolar interaction, which contain valuable structural information.

We address these problems, on one side implementing novel solid-state NMR experiments based on proton detection, on the other developing decoupling, recoupling and polarization-transfer methods which are best suited for fast MAS conditions.

Collaboration with external page Ago Samoson (Tallinn University of Technology, Estonia).