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In the example of ion-radical pairs (IRPs) formed in electron-transfer quenching of triplet states of the dyes methylene blue and eosin (electron acceptors) by phthalohydrazides (electron donors) in aqueous caustic solutions, it has been found that phthalohydrazide radicals are deprotonated directly in the IRP during their lifetime by the external base (OH-), and a study has been made of this reaction. The yields of radicals from the deprotonated IRPs are 2–3.8 times those from the original IRPs; this difference is related to an increase in AG of IRP recombination as a result of deprotonation. In the region of high concentrations of OH-, experimentally determined dependences of the yield of radicals on [OH-] deviate from the relationships calculated with an exponential model of IRP destruction; this deviation is explained by a nonstationary nature of the diffusion of OH- to the IRP immediately after the IRP is formed.

Endohedral metallofullerene Ce@C82dissolved in dimethylformamide or pyridine is reduced to the radical anion. Analysis of hyperfine coupling with the topologically different 13C nuclei indicates the electronic structure with bivalent cerium and the paramagnetic carbon framework Ce2+@C82·3–. The ESR spectra of the radical anions of the functionalized Ce@C82derivatives are detected.