Debye-Hiickel cell model

Together these essentially replace the Poisson-Boltzmann cell model with the Debye-Hiickel bulk model, allowing many more systems to be treated analytically, although not necessarily accurately, and providing considerable insight into the physical characteristics of electrolyte solutions. 

Another attempt to go beyond the cell model proceeds with the Debye-Hiickel-Bjerrum theory [38]. The linearized PB equation is used as a starting point, however ion association is inserted by hand to correct for the non-linear couplings. This approach incorporates rod-rod interactions and should thus account for full solution properties. For the case of added salt the theory predicts an osmotic coefficient below the Manning limiting value, which is much too low. The same is true for a simplified version of the salt free case. 

It was necessary to measure the dielectric constant and density of each solvent mixture studied. Densities were determined in a constant-temperature bath maintained to within 0.02°C. Gay-Lussac pycnometers with a capacity of 25 mL were used for density measurements. Dielectric constants were determined with a Balsbaugh Model 2TN50 conductivity cell having a cell constant of 0.001. A Janz-Mclntyre a-c bridge (17) was used. The dielectric constants and densities of the solvents are listed in Table I, along with the constants A and B of the Debye-Hiickel theory. 

The Debye-Hiickel approximation can be improved by considering the full Poisson-Boltzmann approach to electrostatic interactions, in which the counterion condensation phenomena are included implicitly. Tests of the Poisson-Boltzmann approach to a cell model of rigid polyelectrolytes [161,162] were done in references [163 165] by performing molecular... 

Cell Model Debye-Hiickel Screening Constant... 

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