Nuclear Magnetic Resonance

**Semantic type:** Natural Phenomenon or Process

**Definition:** A physical phenomenon involving the interaction of atomic nuclei placed in an external magnetic field with an applied electromagnetic field oscillating at a particular frequency. Magnetic conditions within the material are measured by monitoring the radiation absorbed and emitted by the atomic nuclei. It is the underlying principle of Magnetic Resonance Imaging (MRI).

**Synonyms:** - Magnetic Resonance - NMR