title: Liquid-crystal mediated nanoparticle interactions and gel formation.
abstract: Colloidal particles embedded within nematic liquid crystals exhibit strong anisotropic interactions arising from preferential orientation of nematogens near the particle surface. Such interactions are conducive to forming branched, gel-like aggregates. Anchoring effects also induce interactions between colloids dispersed in the isotropic liquid phase, through the interactions of the pre-nematic wetting layers. Here we utilize computer simulation using coarse-grained mesogens to perform a molecular-level calculation of the potential of mean force between two embedded nanoparticles as a function of anchoring for a set of solvent conditions straddling the isotropic-nematic transition. We observe that strong, nontrivial interactions can be induced between particles dispersed in mesogenic solvent, and explore how such interactions might be utilized to induce a gel state in the isotropic and nematic phases.
authors.affiliation: Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706-1691, USA.
authors.forename: Jonathan K
authors.initials: JK
authors.lastname: Whitmer
authors.forename: Abhijeet A
authors.initials: AA
authors.lastname: Joshi
authors.forename: Tyler F
authors.initials: TF
authors.lastname: Roberts
authors.forename: Juan J
authors.initials: JJ
authors.lastname: de Pablo
mesh_terms: D005782:Gels / Q000138:chemical synthesis* / Q000737:chemistry; D050866:Liquid Crystals / Q000737:chemistry*; D056004:Molecular Dynamics Simulation; D053758:Nanoparticles / Q000737:chemistry*
chemical_list: D005782:Gels