Basics of NMR Spectroscopy (for Novices)

The NMR phenomenon is based on the detection of how an atomic nucleus with a non-null spin interacts with a magnetic field. Thus, NMR spectroscopy can be used to study any chemical element having a spinning nucleus. For organic chemists, this is a technique par excellence employed to retrieve the structure of “small” molecular compounds, by detecting 1H and 13C nuclei; however, with a few adaptations, it constitutes a very useful tool of general applicability for the detection of other elements and for the characterization of complex systems such as supramolecular aggregates, biomolecules and organic or inorganic materials. This, in turn, opens the way to diverse applications in industrial, biomedical and environmental contexts. NMR is a very versatile technique: indeed, it should be rather considered as a constellation of different interrelated techniques, e.g. 1D and 2D (correlation spectroscopy) spectroscopy in the liquid phase, NOEbased, TOCSY and solid-state techniques, relaxometry, and so on. Any chemist is perfectly aware of the topics covered in this chapter; therefore, the following presentation aims at outlining the fundamental concepts and aspects of modern NMR for those people (engineers, biologists, environmentalists, physicians, etc.) who are not familiar with the subject. For a more detailed and exhaustive discussion, interested readers are strongly advised to consult the reference textbooks listed at the end of this presentation.