|electron spin resonance|
|See also nuclear magnetic resonance ESR a technique for investigating paramagnetic substances by subjecting them to high-frequency radiation in a strong magnetic field. Changes in the spin of unpaired electrons cause radiation to be absorbed at certain frequencies|
|an arrangement of five objects, as trees, in a square or rectangle, one at each corner and one in the middle.|
|a calculus or concretion found in the stomach or intestines of certain animals, esp. ruminants, formerly reputed to be an effective remedy for poison.|
electron spin resonance n.
Abbr. ESR A spectrometric method, based on measurement of the spins of unpaired electrons in a magnetic field, for detecting and estimating free radicals in organic reactions.