Incorporating Benchtop NMR Spectrometers in the Undergraduate Lab: Understanding Resolution and Circumventing Second-Order Effects

Nuclear magnetic resonance (NMR) spectroscopy is commonly introduced to students in the classroom, but its hands-on use in undergraduate laboratories is far less common. The significant costs to purchase and maintain a traditional high-field NMR spectrometer means that many institutions cannot offer this service to their students. Benchtop NMR spectrometers represent a very powerful alternative at a fraction of the cost and laboratory footprint. However, concerns about resolution and managing second-order effects can hamper its incorporation into the undergraduate curricula. Herein, we describe how resolution at the benchtop level differs from traditional high-field instruments and provide a thorough, tabulated list of 204 molecules which exhibit little to no second-order effects at the lower magnetic fields utilized in benchtop NMR spectroscopy.