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Discretization Dependence of Criticality in Model Fluids: a Hard-core Electrolyte

Young C. Kim·Michael E. Fisher
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Abstract

Grand canonical simulations at various levels, $ζ=5$-20, of fine- lattice discretization are reported for the near-critical 1:1 hard-core electrolyte or RPM. With the aid of finite-size scaling analyses it is shown convincingly that, contrary to recent suggestions, the universal critical behavior is independent of $ζ$ $(\grtsim 4)$; thus the continuum $(ζ\to\infty)$ RPM exhibits Ising-type (as against classical, SAW, XY, etc.) criticality. A general consideration of lattice discretization provides effective extrapolation of the {\em intrinsically} erratic $ζ$-dependence, yielding $(\Tc^ {\ast},\rhoc^{\ast})\simeq (0.0493_{3},0.075)$ for the $ζ=\infty$ RPM.

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BibTeXRIS

Young C. Kim, Michael E. Fisher. 2004-02-10. Discretization Dependence of Criticality in Model Fluids: a Hard-core Electrolyte. https://doi.org/10.1103/physrevlett.92.185703

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