title: Phase separations in liquid crystal-colloid mixtures.
abstract: We present a mean-field theory to describe phase separations in mixtures of a nematic liquid crystal and a colloidal particle. The theory takes into account an orientational ordering of liquid crystals and a crystalline ordering of colloidal particles. We calculate phase diagrams on the temperature-concentration plane, depending on interactions between a liquid crystal and a colloidal surface and a coupling between nematic and crystalline ordering. We find various phase separation processes, such as a nematic-crystal phase separation and nematic-isotropic-crystal triple point. Inside binodal curves, we find new unstable and metastable regions which are important in phase ordering dynamics. We also find a stable nematic-crystalline (NC) phase, where colloidal particles dispersed in a nematic phase can form a crystalline structure. The coexistence between two NC phases with different concentrations can be appear though the coupling between nematic and crystalline ordering.
authors.affiliation: Department of Bioscience and Bioinformatics, Faculty of Computer Science and System Engineering, Kyushu Institute of Technology, Kawazu 680-4, Iizuka, Fukuoka 820-8502, Japan. matuyama@bio.kyutech.ac.jp
authors.forename: Akihiko
authors.initials: A
authors.lastname: Matsuyama
authors.forename: Ryota
authors.initials: R
authors.lastname: Hirashima
mesh_terms: D000465:Algorithms; D003102:Colloids / Q000737:chemistry*; D003460:Crystallization; D050866:Liquid Crystals / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry*; D044367:Phase Transition; D013499:Surface Properties; D013696:Temperature
chemical_list: D003102:Colloids