Reorganization outer-shell

Secondly, the intrinsic barrier is usefully separated into so-called "inner-shell and "outer-shell components, AG and AG, respectively. The former is associated with reorganization of the internal reactant coordinates (e.g. changes in metal-ligand bond distances, reactant conformation), whereas the latter arises from alterations in the polarization of surrounding solvent molecules. The former can be estimated on the basis of a simple harmonic oscillator model from [la]... 

The outer-shell intrinsic reorganization energy, AG, is usually treated on the basis of the dielectric continuum treatment. For one-electron electrochemical reactions, this yields [32]... 

Another simple relationship can be recovered for reactions where the outer-shell reorganization provides the only component of AG. If reactant electrode imaging can be neglected (so that R 1 -> 0) and the internuclear distance, Rh, is equal to twice the reactant radius, then the quantity C in eqn. (43) equals AG, so that simply... 

It was found that in the overall energy of reorganization, there is a significant contribution from the inner-shell component, roughly comparable with the outer-shell reorganization. 

The reorganization parameter is usually broken down into inner-shell (vibrational) and outer-shell (solvational) components. 

The inner-shell reorganization energy is generally treated within an harmonic approximation [18], The outer-shell reorganization energy depends upon the properties of the solvent. When a continuum model for the solvent is used Aout is a function of the dielectric properties of the medium, the distance separating the donor and acceptor sites, and the shape of the reactants. 

Role of the Solvent The Outer Shell Reorganization Energy... 

An interesting consequence of the additive formulation in Eqs. (66) and (67) of the reorganization energy for an A/D electron transfer is that it may be broken in three components the outer shell reorganization, and and A,P, which involve the... 

In Eq. (89), Ao and A are the outer shell reorganization energies for the respective isotopic electron transfers, defined similarly as Ao in Eq. (72). Thus as soon as the equivalent radii for the acceptor and the donor do not differ by a factor larger than 2, one gets within about 10% precision ... 

The free-energy barrier for the thermal-electron transfer AG is made up of two parts, the inner-shell and the outer-shell (solvent) reorganization energy " ... 

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