Electrostatic free energy change

Levy, R. M., Belhadj, M., Kitchen, D. B. Gaussian fluctuation formula for electrostatic free energy changes. J. Chem. Phys. 95 (1991) 3627-3633... 

The electrostatic free energy change required to bring the two species (regarded as spheres) to their distance (r12) in the collision complex (Fig. 4) is... 

Cmp and Dmp are specific constants related to the dimensions of the macromolecule, while the coefficient Amp is inversely dependent on protein size. A similar relationship can be derived for the stationary phase component of the change in the Gibbs free energy due to electrostatic effects (AG >sp><), although the precise relationship between salt concentration in the mobile phase and activity coefficient of the protein when bound to the sorbent may take a more complex form. The electrostatic free-energy change associated with the chromatographic retention process then can be expressed as... 

A very similar equation was introduced by Katchalsky et al. (1954), in which an attempt is made to use the Hermans-Overbeek equation (Hermans and Overbeek, 1948) to compute the actual electrostatic free energy change that can be attributed to the accumulation of negative charge in a flexible linear poly electrolyte. This equation is of the general form ... 

The electrostatic free energy change in this equation differs somewhat from that used by Caselli et Indeed, Leodidis and Hatton introduce the excess free energy of the bulk water whereas Caselli et consider only the water pool contribution. Moreover, the main difference is the model for electrostatic interactions. Leodidis and Hatton eliminated the Poisson-... 

R. M. Levy, M. Belhadj, and D. B. Kitchen, ]. Ghem. Phys., 95, 3627 (1991). Gaussian Fluctuation Formula for Electrostatic Free Energy Changes in Solution. 

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