Theory of collective diffusion in two-dimensional colloidal suspensions
نویسندگان
چکیده
We consider many-particle diffusion in 2D colloidal suspensions with hydrodynamic interactions within a mode-coupling approach. We focus on the behaviour of the effective scaled collective diffusion coefficient DC(ρ)/D0 as a function of the density of the colloids ρ, where D0 is the single-particle diffusion coefficient. We find that DC(ρ) is strongly coupled to hydrodynamical conservation laws and is distinctly different from the purely dissipative case without hydrodynamic interactions, in that it may display a minimum at intermediate densities. Our results for the density dependence of DC(ρ)/D0 are in good agreement with recently published simulation data.
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