Long-time translational self-diffusion in isotropic dispersions of colloidal rods

摘要

A dispersion of fluorescent colloidal silica coated boehmite rods with length L approximate to 325 nm and diameter D approximate to 46 nm, dispersed in dimethylformamide, is synthesized. The concentration dependence of the long-time translational self-diffusion coefficient Df is measured with fluorescence recovery after photobleaching up to a rod volume fraction phi = 0.22. A linear dependence of D-s(L) on concentration is found up to (L/D)phi=1. At higher concentration D-s(L) levels off and decreases to 3% of its value at infinite dilution for (L/D)phi=1.5.