Structural Characterization of New Ferroelectric Liquid-Crystalline Siloxanes

Mohammed Ibn-Elhaj; Antoine Skoulios; Daniel Guillon; Joanna Newton; Philip Hodge; Harry J. Coles

doi:doi:10.1051/jp2:1996181

Issue		J. Phys. II France Volume 6, Number 2, February 1996


Page(s)		271 - 279
DOI		https://doi.org/10.1051/jp2:1996181

DOI: 10.1051/jp2:1996181
J. Phys. II France 6 (1996) 271-279

Structural Characterization of New Ferroelectric Liquid-Crystalline Siloxanes

Mohammed Ibn-Elhaj¹, Antoine Skoulios¹, Daniel Guillon¹, Joanna Newton², Philip Hodge² and Harry J. Coles²

¹ Institut de Physique et Chimie des Matériaux de Strasbourg CNRS: UMR 380046, Groupe des Matériaux Organiques, 23 rue du Loess, 67037 Strasbourg Cedex, France
² Liquid Crystal Group, Physics Department, The University, Manchester, M13 9PL, UK

(Received 6 June 1995, received in final form 16 October 1995, accepted 23 October 1995)

Abstract
In a previous paper [1] we reported the structural study of new smectogenic molecules containing three distinct parts, an aromatic core, a central paraffin chain and a siloxane endgroup. In the present paper we report the structural characterization of new ferroelectric liquid crystalline siloxanes containing, in addition to these three parts, a branched aliphatic tail. These low molar mass chiral organosiloxane mesognes and their racemic analogs have been characterized using X-ray diffraction both on powder and oriented samples. The chiral (and achiral) compounds exhibit enantiotropic ferroelectric smectic C ^* (or smectic C) mesophases with high tilt angles at low temperatures and over a broad temperatrue range.