Density-functional approach to smectic order in an aligned hard-rod fluid

Abstract

The occurrence of smectic order in a system of perfectly aligned hard cylinders is studied with use of a bifurcation analysis of the free-energy functional in the second virial coefficient approximation. This approximation is shown to yield a second-order transition of mean-field type towards a smectic phase. The influence of higher-order terms in the density expansion of the free-energy functional is considered by calculating the shift in the location of the bifurcation point associated with the transition, when the third- and fourth-order terms in the one-particle density are taken into account.