Effect of repulsive and attractive interactions on depletion forces in colloidal suspensions: a density functional theory treatment.

The author employs density functional theory to study colloidal interactions in solution. Hardcore Yukawa potentials with soft tails, either repulsive or attractive, are used to model colloid-solvent and solvent-solvent interactions. We analyze the effect of these interactions on the solvent-mediated potential of mean force between two colloids in solution. Overall, theory is shown to be in good agreement with recent simulation data. We use the theory to study the density dependence of the colloid-colloid second virial coefficient.