Surface phase transitions in polydisperse hard rod fluids

Abstract

I study the effect of length polydispersity in the surface phase diagram of hard rods interacting with a hard wall. The properly extended interface Gibbs-Duhem equation for a polydisperse system allows us to predict the behaviour of the surface tension as a function of the bulk density at the the wall-isotropic interface. Two groups of qualitative different bulk and surface phase diagrams are calculated from two families of parametrized length distribution functions $p(l)$. This parameterization controls the law of decay at large $l$. I also study the segregation due to polydispersity at the isotropic-nematic interface and the capillary nematization phenomena as a function of polydispersity.

20 pages, 27 figures