Marketing

Quantum mechanics

Sediment

Colloid

Chemical physics

SPHERES

Materials science

Brownian motion

Statistical physics

Geology

Business

Oceanography

Physical chemistry

Paleontology

Thermodynamics

Physics

Diffusion

Astronomy

Molecular dynamics

Sedimentation

Colloidal particle

Computational chemistry

Particle (ecology)

Brownian dynamics

Self-diffusion

Chemistry

Self-service

Mechanics

Hard spheres

The Journal of Chemical Physics

We study self-diffusion and sedimentation in colloidal suspensions of nearly hard spheres using the multiparticle collision dynamics simulation method for the solvent with a discrete mesh model for the colloidal particles (MD+MPCD). We cover colloid volume fractions from 0.01 to 0.40 and compare the MD+MPCD simulations to experimental data and Brownian dynamics simulations with free-draining hydrodynamics (BD) as well as pairwise far-field hydrodynamics described using the Rotne-Prager-Yamakawa mobility tensor (BD+RPY). The dynamics in MD+MPCD suggest that the colloidal particles are only partially coupled to the solvent at short times. However, the long-time self-diffusion coefficient in MD+MPCD is comparable to that in experiments, and the sedimentation coefficient in MD+MPCD is in good agreement with that in experiments and BD+RPY, suggesting that MD+MPCD gives a reasonable description of hydrodynamic interactions in colloidal suspensions. The discrete-particle MD+MPCD approach is convenient and readily extended to more complex shapes, and we determine the long-time self-diffusion coefficient in suspensions of nearly hard cubes to demonstrate its generality.

Diffusion and sedimentation in colloidal suspensions using multiparticle collision dynamics with a discrete particle model