Isotropic distributions in hcp crystals

On the Isotropic-Nematic Transition in Polymer Liquid Crystals

A system of polymers dissolved in liquid crystal is studied in the isotropic phase. A mean eld theory is proposed which undergoes spontaneous breaking of the rotational symmetry and reduces to the theory of polymer nematics. In order to eliminate closed loops of polymers from entering into the theory, the polymers are replicated n times and then n is taken to zero similarly to the procedures of...

Hidden photoalignment of liquid crystals in the isotropic phase.

We found the effect of a hidden photoalignment of a dye-doped nematic liquid crystal (LC) on a nonphotosensitive polymer surface after polarized irradiation of the cell in the isotropic phase. We observed that irradiation resulted in a uniform planar orientation of the LC after cooling to the mesophase. The direction of a light-induced easy axis on the polymer can be either parallel or perpendi...

Electro-Optic Kerr Effect in Polymer-Stabilized Isotropic Liquid Crystals

Vacancy defect distributions in bulk ZnO crystals

We have used positron annihilation spectroscopy to study vacancy defects in ZnO single crystals grown by various methods from both commercial and academic sources. The combination of positron lifetime and Doppler broadening techniques with theoretical calculations provides the means to deduce both the identities and the concentrations of the vacancies. The annihilation characteristics of the Zn...

The isotropic-nematic transition in charged liquid crystals

2014 We discuss the phase diagram of a concentrated system of rods interacting via a Coulomb potential, and demonstrate the existence of a first-order isotropic-nematic transition. J. Physique 43 (1982) 651-654 AVRIL 1982, Classification Physics Abstracts 05.20 61.30C 64.70E