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Chemistry LibreTexts

Electron Paramagnetic Resonance

Electron Paramagnetic Resonance (EPR) is a remarkably useful form of spectroscopy used to study molecules or atoms with an unpaired electron. It is less widely used than NMR because stable molecules often do not have unpaired electrons (i.e., paramagnetic). However, EPR can be used analytically to observe labeled species in situ either biologically or in chemical reactions.