Hydrogen Atom Transfers by Tautomerism

C-N(H) and vice versa. This simultaneous transfer of electrons requires that such an H-atom transfer (or transfers) occurs within a cyclic H-bonded structure. It points to the first difference between H-atom transfers and proton transfers, for which no such requirement exists. 

Sandorfy, in Schuster, G. Zundel and C. Sandorfy (Eds.), The Hydrogen Bond Recent Developments in Theory and Experiments, Vol. II, Ch. 13, North Holland, Amsterdam, 1976. 

Chudoba, E. Riedle, M. Pfeiffer and T. Elsaesser, Chem. Phys. Lett., 263 (1996) 622. 

Hayashi, E. Tajkhorsid, E. Pebay-Peroula, A. Royant, E. M. Landau, J. Navarro and K. Schulten, J. Phys. Chem. B, 105 (2001) 10124. 

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