Nucleophilic attack via single-electron transfer

The facile nucleophilic displacement of chloride from alkyl chlorine compounds (all uncharged atoms) by HO (-1-charge O) to give an alcohol (all uncharged atoms) is a charge-transfer process via electron transfer from the HO to the chlorine atom of RCl O 

The data of Figs. 2-1 and 2-2 and of Tables 2-3 and 2-4 provide persuasive evidence that the electron-transfer and atom-transfer chemistry for dioxygen species and mono-oxygen species is strongly dependent upon proton activity, anion solvation, and relative X-OO and Y-O covalent bond energies. Hence, the solvation energy of HO is 22.5 kcal less in acetonitrile than in water, which causes the HO-/HO- redox potential to be 4-0.92 V versus NHE in MeCN instead of 4-1.89 V versus NHE in H2O. 

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