electron spin resonance

noun Physics.

1. the flipping back and forth between two spin directions of electrons in a magnetic field when electromagnetic radiation of the proper frequency is applied. Abbreviation: ESR

noun

1. 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 frequenciesAbbreviation: ESR See also nuclear magnetic resonance

n.

1. 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.