Home CV Research People Teaching Blog

Schmidt - Browse papers with the paper browser

[bare list] [illustrated] [by topic]
    Reference [<] [>] [x] : Figure [<] [>] [x]

    32. Model colloid-polymer mixtures in porous matrices: density functional versus integral equations
    M. Schmidt, E. Schöll-Paschinger, J. Köfinger, and G. Kahl, J. Phys.: Condens. Matt. 14, 12099 (2002).
    Locate in [bare] [illustrated] list. Get [full paper] as pdf.

    Abstract. We test the accuracy of a recently proposed density functional (DF) for a fluid in contact with a porous matrix. The DF was constructed in the spirit of Rosenfeld's fundamental measure concept and was derived for general mixtures of hard core and ideal particles. The required double average over fluid and matrix configurations is performed explicitly. As an application we consider a model mixture where colloids and matrix particles are represented by hard spheres and polymers by ideal spheres. Integrating over the degrees of freedom of the polymers leads to a binary colloid-matrix system with effective Asakura-Oosawa pair potentials, which we treat with an integral-equation theory. We find that partial pair correlation functions from both theories are in good agreement with our computer simulation results, and that the theoretical results for the demixing binodals compare well, provided the polymer-to-colloid size ratio, and hence the effect of many-body interactions neglected in the effective model, is not too large. Consistently, we find that hard (ideal) matrix-polymer interactions induce capillary condensation(evaporation) of the colloidal liquid phase. [figures]


    Read the [full paper] as pdf.

    Fluids in random media

    The density functional theory for quenched-annealed mixtures [24] relates the quenched components to a random porous medium and the annealed components model to an adsorbate fluid (mixture). See [46] for the explicit relation to the the replica trick. Colloid-polymer mixtures were studied in bulk random matrices [32], exhibiting (gas-liquid) interfaces [41], and wetting properties at porous substrates [56]. Rods were immersed in quenched sphere matrices [54], and spheres were immersed in random fibre networks [39]. Freezing is hindered in the presence of disorder [38]. See [33] for the related non-equilibrium process of random sequential adsorption.

    [more]

Legal. The material on this website is intended as a scientific resource for the private use of individual scholars. None of it may be used commercially, or for financial gain. Some of the material is protected by copyright. Requests for permission to make public use of any of the papers, or material therein, should be sought from the original publisher, or from M. Schmidt, as appropriate.
MS, 20 Apr 2009.