Probes for solid-state NMR have the ability to spin samples very rapidly at the magic angle. Spinning frequencies
up to 23KHz are possible with the probes in our facility.
- High-Resolution solid-state NMR relies upon the ability to rapidly rotate the sample about the magic angle of 54.7356 degrees, relative to the magnetic field. If spinning is faster than the inherent line-broadening mechanisms in the solid (primarily dipolar coupling and Chemical Shift Anisotropy, or CSA), then the these interactions disappear (for spin I=1/2 nuclei).
- Samples are loaded into a small, ceramic rotor, with sealed caps on both ends (see photo, lower left).
- The rotor is inserted into the stator assembly (see photo, upper left). Compressed air (or nitrogen) passes through tiny holes to float the sample on a bearing of air. The drive holes are visible in the photo the the left (top), which pass air over the drive-flutes on the cap (shown in lower photo).
- The solid-state NMR probes are engineered to handle much higher radiofrequency (Rf) power, which is required to excite and decouple the frequency bandwidths necessary for solid-state NMR.