Electron Paramagnetic Resonance spectroscopy, lanthanide ions

Electron paramagnetic resonance (EPR) or electron spin resonance (ESR) spectroscopy is suitable for the study of systems containing unpaired electrons, i.e., free radicals, transition metal ions, lanthanide metal ions, transuranium ions and complexes. Systems containing transition metal ions or lanthanide metal ions are particularly important in the study of solution structure. 

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