The corrected Enskog theory and the transport properties of molecular liquids

Analytical expressions for the transport coefficients of liquids based on the corrected Enskog theory have been used in order to determine the self-diffusion coefficient (D) for molecular liquids as a function of density and temperature. The liquids considered are those composed of linear molecules and NH3. The calculated D values agree with the experimental ones for those molecular liquids for which experimental self-diffusion data are available. The translational part of the thermal conductivity (λtrans) has also been calculated and compared with the experimental thermal conductivity (λ). It turns out that λtrans for diatomic molecular liquids practically represents the whole of λ in a substantial fraction of the liquid range, indicating that the internal degrees of freedom hardly contribute to the thermal conductivity in these dense liquids. A comparison is made with recently published results based on the modified Enskog theory.