Density-Functional Theory for Nematic andSmectic−AOrdering of Hard Spherocylinders

Abstract

A density-functional theory, based on the smoothed density approximation, is presented in order to study phase transitions in systems of hard spherocylinders with full translational and orientational degrees of freedom. We find both the nematic-isotropic and the $\mathrm{n}\mathrm{e}\mathrm{m}\mathrm{a}\mathrm{t}\mathrm{i}\mathrm{c}-\mathrm{S}\mathrm{m}\mathrm{e}\mathrm{c}\mathrm{t}\mathrm{i}\mathrm{c}-A$ phase transition in a wide range of length-to-width ratios $\frac{L}{D}$. The predictions of our theory are in good agreement with results of computer simulations and we recover Onsager's limit of $\frac{L}{D}\to \infty$. We also make some comments about application of the theory to systems of hard ellipsoids.