Volumetric properties of mixtures of simple molecular fluids

Abstract

The excess volumes, V^E, of several binary mixtures of simple molecular fluids have been measured as a function of composition and temperature. The results cannot be explained qualitatively using perturbation theories based on mixtures of spherical molecules and multipoles. The interplay of different kinds of anisotropy in the intermolecular potential seems to display complicated behaviour. A generalized van der Waals equation, a model based on a lattice with holes and a semiempirical equation of state have been used for fitting the experimental results satisfactorily. However, none of the models manages to predict other excess functions even for these relatively simple fluids.