Polar liquid crystalline materials can be used in optical and electronic applications, and recent interest has turned to formation strategies that exploit the shape of polar molecules and their interactions to direct molecular alignment. For example, banana-shaped molecules align their molecular bent within smectic layers, whereas conical molecules should form polar columnar assemblies. However, the flatness of the conical molecules used until now and their ability to flip have limited the success of this approach to making polar liquid crystalline materials. Here we show that the attachment of five aromatic groups to one pentagon of a C(60) fullerene molecule yields deeply conical molecules that stack into polar columnar assemblies. The stacking is driven by attractive interactions between the spherical fullerene moiety and the hollow cone formed by the five aromatic side groups of a neighbouring molecule in the same column. This packing pattern is maintained when we extend the aromatic groups by attaching flexible aliphatic chains, which yields compounds with thermotropic and lyotropic liquid crystalline properties. In contrast, the previously reported fullerene-containing liquid crystals all exhibit thermotropic properties only, and none of them contains the fullerene moiety as a functional part of its mesogen units. Our design strategy should be applicable to other molecules and yield a range of new polar liquid crystalline materials.

Self‐organized anisotropic ion‐conductive materials can be formed by the interactions between a conventional ionic liquid and hydroxyl‐terminated mesogenic compounds. Anisotropic ionic conductivities could be measured for samples that formed oriented monodomains in the measurement cell. The Figure shows the ionic liquid and mesogenic compound in the cells used for these measurements. (See also cover)

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Ellipsoidal anatase TiO2 nanoparticles of different aspect ratios were obtained by the gel-sol method in the presence of amino acids in which the resulting particles were basically single crystals, but highly rough surfaces or partly polycrystalline structures were observed with a high concentration of glutamic acid or aspartic acid.

The first simple-cubic liquid crystal was obtained by coating monodisperse Au nanoparticles (NPs) with a thick corona of amino-substituted organic dendrons. This unusual structure was determined by grazing-incidence diffraction and electron density reconstruction and explained by analyzing the radial density profile of the corona. Another novel structure is proposed for the phase preceding the cubic one: a hexagonal superlattice composed of alternating dense and sparse strings of Au NPs.

Amphiphilic ionic liquid derivatives form self-organized lamellar liquid crystals with room temperature ionic liquids. The ionic conductivities along the smectic layers have been obtained for the samples aligned in the cells with electrodes. The highest value is 4.3×10-2 S cm-1 at 139 °C.

A novel organic-inorganic hybrid thermotropic liquid crystal (LC) is developed by the hybridization of an organic amine with a mesogenic core and an acicular anisotropic TiO2 particle through the adsorption of the amino group to the surfaces of the TiO2. The hybrid LC shows nematic phases in wide ranges of temperatures. Variable-temperature small-angle X-ray measurements reveal that the formation of the one-dimensional nematic order of the acicular particles on a submicrometer scale induces thermotropic liquid crystallinity. This technique would lead to induction of dynamic functions in inorganic particles.

Helical self‐assembled columns form supramolecular chiral cubic and columnar liquid‐crystalline phases (see picture). The complexation of hydrogen‐bonded disks of folic acid derivatives that have oligo(glutamic acid) moieties and lipophilic alkyl chains with nonchiral ions leads to the self‐assembly of chiral Pm3n cubic and hexagonal columnar structures.