A Landau-de Gennes theory for hard colloidal rods: defects and tactoids

摘要: We construct a phenomenological Landau-de Gennes theory for hard colloidal rods by performing an order parameter expansion of the chemical-potential dependent grand potential. By fitting coefficients to known results Onsager theory, we are not only able describe isotropic-nematic phase transition as function density, including well-known density jump, but also planar interface. The resulting is applied in calculations isotropic core size radial hedgehog defect, dependence linear defects square confinement, and formation nematic droplet background.