Wall-fluid and liquid-gas interfaces of model colloid-polymer mixtures by simulation and theory

摘要: We perform a study of the interfacial properties model suspension hard sphere colloids with diameter sigma(c) and nonadsorbing ideal polymer coils sigma(p) . For mixture in contact planar wall, we obtain from simulations wall-fluid free energy, gamma(wf) , for size ratios q =sigma(p)/sigma(c) =0.6 1, using thermodynamic integration, (excess) adsorption colloids, Gamma(c) polymers, Gamma(p) at wall. The tension liquid-gas interface, gamma(lg) is obtained following three different routes simulations: (i) studying system dependence width according to predictions capillary wave theory, (ii) probability distribution colloid density coexistence grand canonical ensemble, (iii) state points where colloidal liquid wets wall completely, Young's equation relating difference wall-liquid wall-gas tensions, gamma(wl)-gamma(wg) In addition, calculate ,Gamma(c) functional theory scaled particle based on volume theory. Good agreement found between simulation results those while quantitatively deviate but reproduce some essential features. Simulation are all good agreement. Density predicts accuracy high reservoir packing fractions, yields deviations close critical point.