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Reorganizational free energy

The solvent contribution to the reorganizational free energy should be distinguished from the solvent reorganizational energy the relationship between them is... [Pg.1180]

Equation (22) indicates that the entropy contribution to the reorganizational free energy caimot be neglected. For the electron-transfer rate constant, the free energy of activation is... [Pg.1182]

The slope of a plot of K versus, is expected to be 31.9 X 10 cm pm for self-exchange reactions (for which a=b and = 2a). Equation(31) is expected to give the general pattern for solvational contributions to the reorganizational free energy, but it does not take account of entropy, specific solvational effects, the effect... [Pg.1183]

If we assume that the reorganizational free-energy contributions to Eq. 7 are a linear combination of those of the constituent couples, = iXr + Zr )/2, then Vniax can be factored into contributions of the donor and the acceptor. Since the electrode potentials are determined for the separated donor and acceptor species, the actual free-energy change associated with the ion pairs contains a correction for the ground state (Kg) and excited state (A o ) association (a work term that is written in terms of formation constants), Eq. 23. [Pg.330]

Values for the reorganizational free energies based on observed rate constants for selfexchange reactions (Eq. 3) of the couples noted, except (for halides) as indicated =... [Pg.333]

A different issue concerns Lever s reorganizational energies in Table 2) for the vertical ionization processes [10]. These are best-fit energy values for the individual donors and acceptors, and they are, in principle, different from the selfexchange reorganizational free energies (/r" in Table 2). The values of are systematically larger [(+2.4 + 2.6) x 10 cm ] than the values of /r for the anionic donors, but systematically smaller [(—5.4 + 3.0) x 10 cm ] for the cati-... [Pg.334]

X /X" reduction potentials in the bound and ion-pair systems. The actual reduction potentials have been measured for some of the (NH3)5Ru "[NCM (CN)5] complexes [83] and estimated for some of the Ru (NH3)5(X ) " complexes. For these complexes, the effective reorganizational free energies are Xp = (5 0 1.4) x 10 cm , independent of whether X is a halide or a hexacyano complex. Similarly, a plausible correlation line can be drawn through the data in Figure 3 with a slope of one and an intercept of —5 x 10 cm. In the Co complexes, the coordinated halide is probably more difficult to oxidize, while the metal is easier to reduce [73, 94] than in the corresponding ion pair, and the effect of the reduction potentials may not be particularly important. A very rough estimate suggests that Xx/Xp ay... [Pg.336]

The solvent reorganizational free energy contributions (Xs) Inner-sphere or molecular reorganizational contributions... [Pg.657]

The principle factors contributing to the Franck Condon factor are the free energy of reaction (AGda, the contributions of low-frequency vibrational modes to the reorganizational free energy (xs), and the contributions of high-frequency vibrational modes and displacements jhvn and Ah). The contributions of these factors have been extensively discussed, " ... [Pg.683]

Marcus has described the solvent reorganizational free energy (xs) in terms of the repolarization (following the transfer of a charge e) of a dielectric continuum (with index of refraction rj and static dielectric constant D ) around two spherical reactants with radii a and b, separated a distance... [Pg.684]

Figure 9 Plot of nk as a function of free energy for electron-transfer reactions of Ru-65-c)d 65 labeled with different ruthenium polypyridine complexes. The solid tine shows the theoretical dependence of equation (1) calculated with a reorganizational energy of 0.94 eV and a distance r of 13 A. The open boxes are for the reactions involving the excited state, = ki, and the filed boxes are for the thermal back reactions, ki-i = k2, all determined at 22 °C. (Reprinted with permission from Ref. 55. 1993 American Chemical Society)... Figure 9 Plot of nk as a function of free energy for electron-transfer reactions of Ru-65-c)d 65 labeled with different ruthenium polypyridine complexes. The solid tine shows the theoretical dependence of equation (1) calculated with a reorganizational energy of 0.94 eV and a distance r of 13 A. The open boxes are for the reactions involving the excited state, = ki, and the filed boxes are for the thermal back reactions, ki-i = k2, all determined at 22 °C. (Reprinted with permission from Ref. 55. 1993 American Chemical Society)...

See other pages where Reorganizational free energy is mentioned: [Pg.1178]    [Pg.1180]    [Pg.1180]    [Pg.321]    [Pg.1177]    [Pg.1179]    [Pg.1179]    [Pg.661]    [Pg.661]    [Pg.684]    [Pg.367]    [Pg.1178]    [Pg.1180]    [Pg.1180]    [Pg.321]    [Pg.1177]    [Pg.1179]    [Pg.1179]    [Pg.661]    [Pg.661]    [Pg.684]    [Pg.367]    [Pg.211]    [Pg.438]    [Pg.341]    [Pg.166]    [Pg.328]    [Pg.45]    [Pg.316]    [Pg.1182]    [Pg.1190]    [Pg.134]    [Pg.331]    [Pg.342]    [Pg.564]    [Pg.102]    [Pg.104]    [Pg.108]    [Pg.1181]    [Pg.1189]    [Pg.356]    [Pg.9]    [Pg.17]    [Pg.4]    [Pg.7]    [Pg.10]    [Pg.664]   
See also in sourсe #XX -- [ Pg.263 , Pg.281 , Pg.401 , Pg.402 , Pg.438 ]




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Reorganizational energy

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