Implementation of Earth's Field NMR Spectroscopy in an Undergraduate Chemistry Laboratory

Earth's field nuclear magnetic resonance (EFNMR) spectroscopy offers students a unique opportunity to consolidate their understanding of NMR spectroscopic theory through hands-on practice with a simple spectrometer. A comprehensive, 6 h experiment is presented for the introduction of low-field NMR techniques, covering spectroscopy, relaxivity, and imaging experiments in the Earth's magnetic field. This multifaceted practical session explores the concepts of free induction decay, pulse sequences, field homogeneity, relaxation times, J-coupling, and magnetic resonance imaging (MRI), which are reinforced through a series of experiments carried out within an undergraduate teaching laboratory. Students are required to alter parameters as they see fit in order to obtain data, ensuring their understanding of the theory behind NMR spectroscopy. The challenges overcome for the implementation of EFNMR spectroscopy in a modern undergraduate laboratory are also discussed, and detailed instructions are included for spectrometer setup.