nuclear magnetic resonance

scientific technique

Also known as: NMR

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Last updated

Oct. 2, 2026 •History

nuclear magnetic resonance (NMR), selective absorption of very high-frequency radio waves by certain atomic nuclei that are subjected to an appropriately strong stationary magnetic field. This phenomenon was first observed in 1946 by the physicists Felix Bloch and Edward M. Purcell independently of each other. Nuclei in which at least one proton or one neutron is unpaired act like tiny magnets, and a strong magnetic field exerts a force that causes them to precess in...