Self-assembled Liquid Crystals Research Articles

Synthesis of a mesoporous composite material prepared by the self-assembly of mineral liquid crystals.

Here we describe the synthesis of a mesoporous composite material using the self-assembly of well defined tubular building blocks obtained from the exfoliation of [Nb6O17(4-)]n sheets.

Observation of resonant tunneling effects on narrow stripe structure of the 8OCB liquid crystal deposited on the (0001) basal plane of highly oriented pyrolitic graphite by scanning tunneling spectroscopy

Abstract Scanning tunneling microscopy and spectroscopy are used to study the self-assembled 8OCB liquid crystal deposited on the (0001) basal plane of highly oriented pyrolitic graphite. In order to minimize the molecule–molecule interactions the single narrow stripe structures of liquid crystal are created and investigated. The I / V measurements recorded over a single narrow stripe show distinct negative resistance regions or nearly flat regions of the tunneling current. This can be a explained by the resonant tunneling model which includes tunneling via discrete energy levels of the molecule. The Coulomb blockade effect is excluded as a mechanism for the occurrence of nearly flat regions on the I / V characteristics.

Structural properties of nanocomposite materials based on a lyotropic liquid crystal

Nanocomposite films with a hexagonal architecture are built by self-assembly and subsequent polymerisation of lyotropic liquid crystals. The hexagonal arrangement is formed by tubes which are filled with water and seperated by a distance between 35 and 42A depending on the monomer cations. The tubes can be filled with organic or inorganic materials which are highly aligned and isolated from each other.

The self-assembly and lyotropic mesomorphism of riboguanylic acids (GMP)

The three isomeric guanylic acids (5'-GMP, 3'-GMP and 2'-GMP) and the 3':5'-cyclic derivative (cGMP) form, in water solution, left-handed columnar aggregates which, at higher concentration, pack to give left-handed cholesteric mesophases. The self-assembly process and liquid crystal formation are discussed in relation to the behaviour of the 2'-deoxy analogues.

A new model for cellulose architecture in some plant cell walls

A new model of rotating fibre components (helicoidal model) is proposed to explain the architecture of some plant cell walls. On the basis of tilting observations under the electron microscope, we establish the validity of this model for the cell wall ofChara vulgaris oospores. We suggest that this model explains the architecture seen in a number of published micrographs from a variety of different plant cell walls. Helicoidal architecture is shown to be distinct from the previously established crossed polylamellate architecture. The diagnostic features of helicoidal architecture are given. Morphogenesis of plant cell walls is discussed, with particular reference to self assembly in cholesteric liquid crystals.