Singular Coexistence-curve Diameters: Experiments and Simulations
نویسنده
چکیده
Precise calculations of the coexistence-curve diameters of a hard-core square-well (HCSW) fluid and the restricted primitive model (RPM) electrolyte exhibit marked deviations from rectilinear behavior. The HCSW diameter displays a |t| singularity that sets in sharply for |t| ≡ |T −Tc|/Tc . 10; this compares favorably with extensive data for SF6, also reflected in C2H6, N2, etc. By contrast, the curvature of the RPM diameter varies slowly over a wide range |t| . 0.1; this behavior mirrors observations for liquid alkali metals, specifically Rb and Cs. Amplitudes for the leading singular terms can be estimated numerically but their values cannot be taken literally.
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