Eur. Phys. J. E 7, 163-166 (2002)
DOI: 10.1140/epje/i200201113

Flow properties of the optically isotropic tetrahedratic phase

H.R. Brand¹, H. Pleiner² and P.E. Cladis<sup>3

1</sup>  Theoretische Physik III, Universität Bayreuth, 95440 Bayreuth, Germany
²  Max-Planck-Institute for Polymer Research, POBox 3148, 55021 Mainz, Germany
³  Advanced Liquid Crystal Technologies, Summit, POB 1314, NJ 07902, USA

brand@uni-bayreuth.de

(Received 31 July 2001)

Abstract
We discuss the coupling between flow and other hydrodynamic variables that can occur in the optically isotropic tetrahedratic phase ( T_d) characterized by a third rank tensor order parameter T_ijk. We point out that an applied electric field or an applied temperature gradient will lead to flow. Reciprocally we predict that, for example, a shear flow applied to a tetrahedratic phase leads to an induced electric field and a temperature gradient. Similarities to recent experimental observations in the vicinity of the isotropic-B7 phase transitions in materials formed by banana-shaped molecules are discussed.

PACS
61.30.Gd - Orientational order of liquid crystals; electric and magnetic field effects on order.
64.70.Md - Transitions in liquid crystals.
05.70.Ln - Nonequilibrium irreversible thermodynamics.


© EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2002