Lattice models of ionic systems with charge asymmetry
نویسندگان
چکیده
The thermodynamics of a charge-asymmetric lattice gas of positive ions carrying charge q and negative ions with charge 2zq is investigated using Debye–Hückel theory. Explicit analytic and numerical calculations, which take into account the formation of neutral and charged clusters and cluster solvation by the residual ions, are performed for z52, 3, and 4. As charge asymmetry increases, the predicted critical point shifts to lower temperatures and higher densities. This trend agrees well with the results from recent Monte Carlo simulations for continuum charge-asymmetric hard-sphere ionic fluids and with the corresponding predictions from continuum Debye–Hückel theory. © 2003 American Institute of Physics. @DOI: 10.1063/1.1558311#
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