title: Density functional for a model colloid-polymer mixture
abstract: We present a density functional theory for mixtures of (hard sphere) colloidal particles and ideal polymers. For this extreme nonadditive system we employ a fundamental measures approach to construct a functional which incorporates the correct dimensional crossover and the exact low density limit. In bulk fluid mixtures the functional yields the same free energy and, therefore, the same gas-liquid (demixing) transition as given by free-volume theory. It generates consistent pair correlation functions; the partial structure factors S(ij)(k) diverge, as k-->0, at the critical point obtained from the free energy. Our results for the structure agree well with those from simulation and Percus-Yevick theory.
authors.affiliation: Institut fur Theoretische Physik II, Heinrich-Heine-Universitat Dusseldorf, Universitatsstrasse 1, D-40225 Dusseldorf, Germany.
authors.initials: M
authors.lastname: Schmidt
authors.initials: H
authors.lastname: Lowen
authors.initials: JM
authors.lastname: Brader
authors.initials: R
authors.lastname: Evans