We study the phase behavior of hard spheres confined between two parallel plates using extensive computer simulations. determine full equilibrium diagram for arbitrary densities and plate separations from one to five hard-sphere diameters free energy calculations. find a first-order fluid-solid transition, which corresponds either capillary freezing or melting depending on separation. The coexisting solid consists crystalline layers with triangular square symmetry. Increasing separation, we...

In simulations and experiments, we study the drying of films containing mixtures large small colloidal particles in water. During drying, mixture stratifies into a layer larger at bottom with smaller on top. We developed model to show that gradient osmotic pressure, which develops dynamically during is responsible for segregation mechanism behind stratification.

Self-stratification is found when drying concentrated binary suspensions of particles only the concentration small and size ratio are high enough.

We study a model suspension of sterically stabilized colloidal particles and nonadsorbing ideal polymer coils, both in bulk adsorbed against planar hard wall. By integrating out the degrees freedom we derive formal expression for effective one-component Hamiltonian colloids. employ an efficient Monte Carlo simulation scheme this mixture based on exact colloid Hamiltonian; i.e., it incorporates all many-body interactions. The character polymer-mediated interactions between colloids yields...

We recently found that crystallization of monodisperse hard spheres from the bulk fluid faces a much higher free energy barrier in four than three dimensions at equivalent supersaturation, due to increased geometrical frustration between simplex-based order and crystal [J.A. van Meel, D. Frenkel, P. Charbonneau, Phys. Rev. E 79, 030201(R) (2009)]. Here, we analyze microscopic contributions fluid-crystal interfacial understand how changes with dimension. find grow dimension identify role...

We describe a test particle approach based on dynamical density functional theory (DDFT) for studying the correlated time evolution of particles that constitute fluid. Our provides means calculating van Hove distribution function by treating its self and distinct parts as two components binary fluid mixture, with `self' component having only one particle, `distinct' consisting all other particles, using DDFT to calculate profiles components. apply this bulk Brownian hard spheres compare...

The non-equilibrium phase behavior of a colloidal hard-sphere fluid under oscillatory shear was investigated in real-space with experiments on poly(methyl methacrylate) (PMMA) suspensions and Brownian Dynamics computer simulations. All the samples both simulation are below coexistence density freezing, so shear-induced crystals out-of-equilibrium melt after cessation shear. physics is therefore fundamentally different from crystallization jammed or glassy systems. Although simulations...

We investigate the drying process of three-component and polydisperse colloidal suspensions using Brownian dynamics simulations. have previously reported (Phys. Rev. Lett. 2016, 116, 118301) on binary mixtures. For mixtures, we found that a gradient osmotic pressure develops during this leads to final film being stratified with layer smaller particles top larger particles. Here, find stratification by size is very general also occurs in ternary name segregation effect diffusiophoresis. In...

We systematically study the relationship between equilibrium and nonequilibrium phase diagrams of a system short-ranged attractive colloids. Using Monte Carlo Brownian dynamics simulations we find window enhanced crystallization that is limited at high interaction strength by slowing down low nucleation barrier. metastable gas-liquid binodal means two-stage process. First, formation dense liquid observed second crystal nucleates within fluid. In addition, colloid packing fractions fluid...

This article addresses wrinkle assisted assembly of core–shell particles with hard cores and soft poly-(N-isopropylacrylamide) shells. As core materials we chose silica as well silver nanoparticles. The assembled structures show that the shells act a separator between inorganic cores. Anisotropic alignment is found on two length scales, macroscopically guided through structure locally due to deformation polymer shell leading smaller inter-core separations compared flat substrates without...

Theoretical approaches to nonequilibrium many-body dynamics generally rest upon an adiabatic assumption, whereby the true is represented as a sequence of equilibrium states. Going beyond this simple approximation notoriously difficult problem. For case classical Brownian dynamics, we present simulation method that allows us isolate and precisely evaluate superadiabatic correlations resulting forces. Application system one-dimensional hard particles reveals importance for well complexity,...

When fabricating photonic crystals from suspensions in volatile liquids using the horizontal deposition method, conventional approach is to evaporate slowly increase time for particles settle an ordered, periodic close-packed structure. Here, we show that greatest ordering of 10 nm aqueous gold nanoparticles (AuNPs) a template larger spherical polymer (mean diameter 338 nm) achieved with very fast water evaporation rates obtained near-infrared radiative heating. Fabrication arrays over areas...

Stratified coatings are used to provide properties at a surface, such as hardness or refractive index, which different from underlying layers. Although time-savings offered by self-assembly approaches, there have been no methods yet reported offer stratification on demand. Here, we demonstrate strategy create self-assembled stratified coatings, can be switched homogeneous structures when required. We use blends of large and small colloidal polymer particle dispersions in water that...

We develop and validate an interatomic potential for ruthenium based on the embedded atom method framework with Finnis/Sinclair representation. confirm that new yields a stable hcp lattice reasonable elastic constants surface stacking fault energies. employ molecular dynamics simulations to bring two surfaces together; one flat other single asperity. compare process of asperity contact formation breaking in Au Ru, materials currently use micro electro mechanical system switches. While is...

We study gel formation in a mixture of equally-sized oppositely charged colloids both experimentally and by means computer simulations. Both the experiments simulations show that mechanism which is formed from dilute, homogeneous suspension an interrupted gas-liquid phase separation. Furthermore, we use Brownian dynamics to relation between equilibrium diagram. find that, regardless interaction range, liquid-gas separation observed as system quenched into state point where metastable. The...

We created hierarchically ordered structures of nanoparticles on smooth planar hydrophilic substrates by drying colloidal dispersions in confinement under macroscopic stamps with microscopically wrinkled surfaces. Experiments were carried out model nanoparticle suspensions that possess high stability and monodispersity. The ranged from single parallel lines particles to arrays dense prismatic ridges. type observed structure could be controlled the particle concentration initial dispersion....

Using Gibbs ensemble Monte Carlo simulations and density functional theory we investigate the fluid-fluid demixing transition in inhomogeneous colloid-polymer mixtures confined between two parallel plates with separation distances one ten colloid diameters covering complete range from quasi-two-dimensional to bulklike behavior. We use Asakura-Oosawa-Vrij model which colloid-colloid interactions are hard-sphere like, while pair potential polymers vanishes. Two different types of confinement...

We perform a study of the interfacial properties model suspension hard sphere colloids with diameter ${\ensuremath{\sigma}}_{c}$ and nonadsorbing ideal polymer coils ${\ensuremath{\sigma}}_{p}$. For mixture in contact planar wall, we obtain from simulations wall-fluid free energy, ${\ensuremath{\gamma}}_{\mathrm{wf}}$, for size ratios $q={\ensuremath{\sigma}}_{p}∕{\ensuremath{\sigma}}_{c}=0.6$ 1, using thermodynamic integration, (excess) adsorption colloids, ${\ensuremath{\Gamma}}_{c}$,...

Abstract A combined molecular dynamics and finite element model simulation of contact adhesion between a rough sphere flat surface has been developed. This uses the results (MD) simulations, obtained using an embedded atom potential, nanoscale Ru-Ru asperity contact. continuum elastic–plastic microscale bump is then created. In this model, roughness represented by system asperities, each which nonlinear hysteretic force vs. distance relationship. The character these relations determined from...

We study the stability of mixtures highly screened repulsive charged spheres and non-adsorbing ideal polymer chains in a common solvent using free volume theory. The effective interaction between colloids an aqueous salt solution is described by Coulomb pair potential, which supplements pure hard-sphere interaction. are treated as that excluded from hard-core interaction, whereas two set to zero. In addition, we investigate phase behaviour colloid–polymer computer simulations, two-body...

We study the kinetics of liquid-to-crystal transformation and gel formation in colloidal suspensions oppositely charged particles. analyse, by means both computer simulations experiments, evolution a fluid quenched to state point phase diagram where most stable is either homogeneous crystalline solid or contact with dilute gas. On one hand, at high temperatures packing fractions, close substitutionally-ordered/substitutionally-disordered solid-solid coexistence line, we find that...

We consider a theoretical model for binary mixture of colloidal particles and spherical emulsion droplets. The hard sphere colloids interact via additional short-ranged attraction long-ranged repulsion. droplet-colloid interaction is an attractive well at the droplet surface, which induces Pickering effect. droplet-droplet hard-core interaction. droplets shrink in time, models evaporation dispersed (oil) phase, we use Monte Carlo simulations dynamics. In experiments, polystyrene were...

A mixture of hard-sphere particles and model emulsion droplets is studied with a Brownian dynamics simulation. We find that the addition nonwetting to suspension pure hard spheres can lead both gas-liquid fluid-solid phase separations. Furthermore, we stable fluid clusters. The stability due saturation attraction occurs when surface completely covered colloidal particles. At larger droplet densities percolation transition observed. resulting networks show dynamical mechanical properties...

We investigate the fluid–fluid demixing phase transition of Asakura–Oosawa model colloid–polymer mixture confined between two smooth parallel hard walls using density functional theory and computer simulations. Comparing fluid profiles for statepoints away from colloidal gas–liquid coexistence yields good agreement theoretical results with simulation data. Theoretical predict consistently a shift binodal critical point towards higher polymer reservoir packing fraction colloid fugacities upon...