Design and Fabrication of a Magic-Angle Spinning Rotor for Solid-State Nuclear Magnetic Resonance Probe

Abstract

Magic-angle spinning (MAS) rotor, a device for high-speed spinning of solid samples, is an essential component of the probes used in solid-state nuclear magnetic resonance (NMR) experiments. In this study, a 4 mm MAS rotor was designed and fabricated in-house. Fluid-solid coupling simulation was carried out to compute the stress and strain in the MAS rotor. Modal analysis was performed to determine the various modes and critical speeds of the MAS rotor. Actual spinning speed test and MAS NMR sampling were carried out to test the performance of the rotor. The results showed that the MAS rotor built in-house could operate normally at a spinning speed up to 14 kHz. The 1H NMR signals of adamantane collected at 4 kHz and 12.5 kHz were collected and compared. These results demonstrated that the 4 mm MAS rotor built in-house could meet the requirements of conventional solid-state NMR experiments.

Keywords

• solid-state nuclear magnetic resonance
• magic angle spinning (mas)
• rotor
• finite element simulation