ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
We present molecular dynamics simulations for two limiting models of ionic solutions: one where the solvent molecules are polar, but nonpolarizable; the other where they are only polarizable (but have no permanent dipole moment). For both models, the static two-body correlation functions, the frequency-dependent dielectric constant and conductivity are calculated and the statistical uncertainty on these quantities estimated for molecular dynamics runs of the order of 105 integration steps. For the case of the polar solvent, the accuracy of the computed static interionic correlation functions allows a valuable test of the hypernetted chain integral equation theory at an ionic concentration of 0.04. The quantitative variation of the fluctuations of polarization and electrical current with change of boundary conditions is evaluated within the context of the second model (polarizable nonpolar solvent). Applying the relationships derived in Part I between the phenomenological coefficients and susceptibilities, it is shown that consistent values for the dielectric constant and electrical conductivity are obtained. The sum rules which generalize the Stillinger–Lovett conditions to ionic solutions are computed and shown to be satisfied in our simulations. The evaluation of these sum rules constitutes an important test of the convergence of the electrolyte system to an equilibrium state.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.457558
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