Density-functional theory of inhomogeneous systems of hard spherocylinders

The smectic-A phase boundaries of a hard-spherocylinder fluid are calculate d using a density-functional theory based on one proposed earlier by Somoza and Tarazona [Phys. Rev. A 41, 965 (1990)]. Our calculations do not employ the translation-rotation decoupling approximation used in previous density -functional theories. The calculated phase boundaries agree well with compu ter simulation results up to aspect ratios L/D approximate to 5 and are in better agreement with the simulations than are previous theories, We genera lize the model fluid by including long-range interactions with quadrupolar orientational symmetry, which are taken into account by mean-field approxim ation. For sufficiently large strength, these interactions produce a smecti c-C phase, which undergoes either a continuous or weakly first-order transi tion to Che smectic-A phase. The theory and numerical methods discussed her e can be applied to the analysis of interfacial phenomena.