What are the benefits of bound (protonation) states for the electron-transfer kinetics?

Dmitry V. Matyushov

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arXiv · 0710.2875

What are the benefits of bound (protonation) states for the electron-transfer kinetics?

Dmitry V. Matyushov

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Abstract

We describe a model of electron transfer reactions affected by local binding to the donor or acceptor sites of a particle in equilibrium with the solution. The statistics of fluctuations of the donor-acceptor energy gap caused by binding/unbinding events are non-Gaussian, and the resulting free energy surfaces of electron transfer are non-parabolic. The band-width of the charge-transfer optical transition is predicted to pass through a maximum as a function of the concentration of binding particles in the solution. The model is used to rationalize recent observations of pH-dependence of electron transfer rates involving changes in the protonation state of the donor-acceptor complex.

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Dmitry V. Matyushov. 2007-10-15. What are the benefits of bound (protonation) states for the electron-transfer kinetics?. https://arxiv.org/abs/0710.2875

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