Details

Autor(en) / Beteiligte

• Donato, Mariangela Di
• Borrelli, Raffaele
• Capobianco, Amedeo
• Monaco, Guglielmo
• Improta, Roberto
• Brahimi, Meziane
• Peluso, Andrea

Titel

Proton Assisted Electron Transfer

Ist Teil von

• Advances in Quantum Chemistry, 1999, Vol.36, p.301-322

Ort / Verlag

United States: Elsevier Science & Technology

Erscheinungsjahr

1999

Beschreibungen/Notizen

• Likely mechanisms for long range electron transfer coupled to proton transfer are investigated. It is shown that, in model systems closely resembling realistic biochemical sequences, the injection of an electron on one end of the H-bonded chain can activate a sequential hopping of protons, which localizes the electronic charge on the opposite end of the chain. Once the additional electron is released to an outer electron acceptor species, then the initial situation is restored, but this time hydrogen atoms and not protons will move back to the original position, carrying the mobile electron from one side of the chain to the other. The dynamics of proton hopping in a model system where the two redox partners are p-monohydroquinone and xanthine, held together by H-bonds with a peptide bridge, shows that the process is fast, the transfer rate being of the order of a few picoseconds.