Depletion interaction mediated by polydisperse rods.

The interaction between a colloidal hard sphere of radius R and a wall or between two spheres in a dilute suspension of infinitely thin rods of length L is calculated numerically. The method allows the study of depletion potentials for any value of L/R and, consequently, the influence of rod length polydispersity can be investigated. It was observed that both the depth and the range of the potential increase drastically if the relative standard deviation σ of the length distribution is larger than 0.25, while the potential is virtually indistinguishable from that caused by monodisperse rods, if σ≤=0.1 [ABSTRACT FROM AUTHOR]