Energy transfer, semiquantitative

Studies of ferredoxin [152] and a photosynthetic reaction center [151] have analyzed further the protein s dielectric response to electron transfer, and the protein s role in reducing the reorganization free energy so as to accelerate electron transfer [152], Different force fields were compared, including a polarizable and a non-polarizable force field [151]. One very recent study considered the effect of point mutations on the redox potential of the protein azurin [56]. Structural relaxation along the simulated reaction pathway was analyzed in detail. Similar to the Cyt c study above, several slow relaxation channels were found, which limited the ability to obtain very precise free energy estimates. Only semiquantitative values were... 

The spectroscopic, kinetic, and thermodynamic data discussed are sufficient to describe semiquantitatively the energy profile of proton transfer to a hydride ligand occurring in solution [29, 35, 36]. Figure 10.10 shows the energy as a function of the proton-hydride distance, varying from the initial state to a final product. The average structural parameters of the initial hydrides and intermediates have been taken from earlier chapters. Since proton-hydride contacts of... 

By considering the kinetic substantiation of the Nernst equation, Audubert[2] and Butler[3] were the first to formulate the semiquantitative concepts concerning the effect of electrode potential on the rate of an electrochemical process. In its present form, the concept of slow discharge was put forward by Erdey-Gruz and Volmer[4]. Their approach was based on a consideration of the effect of potential on the activation energy of an electrode process and led to the introduction of a measure of this effect, viz. the transfer coefficient a. 

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