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Exact relations between charge-density functions determining the total Coulomb energy and the dielectric constant for a mixture of neutral and charged site-site molecules

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 نشر من قبل John D. Weeks
 تاريخ النشر 2009
  مجال البحث فيزياء
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We extend results developed by Chandler [J. Chem. Phys. 65, 2925 (1976)] for the dielectric constant of neutral site-site molecular models to mixtures of both charged and uncharged molecules. This provides a unified derivation connecting the Stillinger-Lovett moment conditions for ions to standard results for the dielectric constant for polar species and yields exact expressions for the small-k expansion of the two-point intermolecular charge-density function used to determine the total Coulomb energy. The latter is useful in determining corrections to the thermodynamics of uniform site-site molecular models simulated with spherically truncated Coulomb interactions.



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