Collect. Czech. Chem. Commun. 2008, 73, 388-400
https://doi.org/10.1135/cccc20080388

Radial Distribution Function in the Hard Sphere Mixtures

Tomáš Boublíka,b

a Department of Chemistry, J. E. Purkinje University, 400 96 Ústí nad Labem, Czech Republic
b Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, 128 43 Prague 2, Czech Republic

Abstract

Equilibrium structures of both homogeneous and heterogeneous systems are, within statistical thermodynamics, characterized by distribution functions. Using the approach proposed recently - based on the determination of the cavity functions for the pair of hard spheres (HS) and the combined body - we studied the effect of different choices of the probe HS (which determines the shape of the combined hard body - enlarged dumbbell) on the prediction of the distribution functions in binary mixtures of HS with the aspect ratio 0.9, ternary mixtures with diameter ratios 1, 0.6 and 0.3, and density profiles of HS mixture with the aspect ratio 2 near a hard wall. It was found that the method, that uses the average geometric functionals determined for the probe HS with individual diameters multiplied by the respective mole fractions yields better results than the approaches based on average probe diameters.

Keywords: Distribution function; Density profile; Hard sphere mixture; Hard sphere near a hard wall; Binary systems; Ternary systems; Enlarged hard dumbbell; Hard sphere chemical potential; Probe diameter; Phase equilibria; Thermodynamics.

References: 24 live references.