Magnetic Resonance (NMR
) spectroscopy has no doubt been the most influential physical method in organic
chemistry during the second half of the 20th century, and has been extensively
used for the structural elucidation and characterization of organic, inorganic,
and biological molecules.
NMR as a non-invasive and non-destructive technique is indispensable in many research fields within chemistry, physics, biology, and medicine. In comparison with X-ray and other forms of spectroscopy (UV, IR and MS), NMR has the advantage of resolving the three-dimensional structures of biological molecules.
It should be noted, that prior to 1955, the structures of organic compounds had to be determined by a combination of chemical tests and degradations.
The parameters obtained from NMR spectra hemical shifts, coupling constants, intensities, relaxation times and diffusion coefficients provide the necessary information for solving a wide variety of problems in chemical and biological sciences.
The application of NMR techniques to problems involving time dependent phenomena includes; conformational analysis, rotational isomerism, restricted rotation, and chemical exchange.