ESR spectra resulting from

Figure 2.8 ESR spectra resulting from the reduction of PhCN (bottom) and />-F-PhCN (top). The top spectrum is identical to that of the 4,4 -dicyanobiphenyl anion radical. (Spectra were simulated using hyperfine couplings with permission from ref. 16, copyright (1963) American Chemical Society.)...

To verify these estimations experimentally, an analysis of electron spin resonance (ESR) spectra resulting from an incomplete reduction of the precisely measured amounts of benzene isotopomers with potassium in THF was conducted (G.R. Stevenson, Espe, Reiter 1986). That approach had been outlined by Chang and Coombe in 1971. The superimposed spectra were analyzed to find the intensity ratio of the signals belonging to the iso-topomeric anion radicals. That ratio produced the concentration ratio of the anion radicals under consideration. 

Figure 2. ESR spectra resulting from mechanical damage of Nylon 6 degraded in various atmospheres. The relative sizes of the spectra were chosen for convenience.

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