| Abstract
| - The shear viscosity formula derived by the density fluctuation theory in previous papers is computed forargon, krypton, and methane by using the self-diffusion coefficients derived in the modified free volumetheory with the help of the generic van der Waals equation of state. In the temperature regime near or abovethe critical temperature, the density dependence of the shear viscosity can be accounted for by ab initiocalculations with the self-diffusion coefficients provided by the modified free volume theory if the minimum(critical) free volume is set equal to the molecular volume and the volume overlap parameter (α) is takenabout unity in the expression for the self-diffusion coefficient. In the subcritical temperature regime, if thedensity fluctuation range parameter is chosen appropriately at a temperature, then the resulting expression forthe shear viscosity can well account for its density and temperature dependence over the ranges of densityand temperature experimentally studied. In the sense that once the density fluctuation range is fixed at atemperature, the theory can account for the experimental data at other subcritical temperatures on the basisof the intermolecular force only; the theory is predictive even in the subcritical regime of temperature. Theoryis successfully tested in comparison with experimental data for self-diffusion coefficients and shear viscosityfor argon, krypton, and methane.
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