It's all about the electrons

摘要

Electron paramagnetic resonance(EPR),also known as electron spin resonance(ESR),was developed as a means of measuring electron spin relaxation times but has become a widely applicable tool.EPR is a nondestructive analytical technique and is the only method available for the direct detection of paramagnetic species.Free radicals and transition metal ions can be identified and quantified in solids,liquids,gases,cells,and in vivo,and EPR can be used to study metal centers and radicals involved in chemical processes in electrochemistry,redox chemistry,photochemistry,biology,and catalysis.