Theory of asymmetric non-additive binary hard-sphere mixtures

Details Theory of asymmetric non-additive binary hard-sphere mixtures Theory of asymmetric non-additive binary hard-sphere mixtures

2001-05-29

arxiv.org/abs/cond-mat/0105547v1

Physics

Condensed Matter

Soft Condensed Matter

Scientific paper

10.1103/PhysRevE.64.051202

We show that the formal procedure of integrating out the degrees of freedom of the small spheres in a binary hard-sphere mixture works equally well for non-additive as it does for additive mixtures. For highly asymmetric mixtures (small size ratios) the resulting effective Hamiltonian of the one-component fluid of big spheres, which consists of an infinite number of many-body interactions, should be accurately approximated by truncating after the term describing the effective pair interaction. Using a density functional treatment developed originally for additive hard-sphere mixtures we determine the zero, one, and two-body contribution to the effective Hamiltonian. We demonstrate that even small degrees of positive or negative non-additivity have significant effect on the shape of the depletion potential. The second virial coefficient $B_2$, corresponding to the effective pair interaction between two big spheres, is found to be a sensitive measure of the effects of non-additivity. The variation of $B_2$ with the density of the small spheres shows significantly different behavior for additive, slightly positive and slightly negative non-additive mixtures. We discuss the possible repercussions of these results for the phase behavior of binary hard-sphere mixtures and suggest that measurements of $B_2$ might provide a means of determining the degree of non-additivity in real colloidal mixtures.

Affiliated with

Also associated with

No associations

Rating

Theory of asymmetric non-additive binary hard-sphere mixtures does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Theory of asymmetric non-additive binary hard-sphere mixtures, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Theory of asymmetric non-additive binary hard-sphere mixtures will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-196947