TY - JOUR
T1 - Electroclinic effect in low molar mass organosiloxane liquid crystals
AU - Carboni, C.
AU - Mehdi, R.
AU - George, A. K.
AU - Al-Harthi, S. H.
AU - Naciri, J.
N1 - Funding Information:
The authors acknowledge the financial supports of Sultan Qaboos University; project IG/SCI/PHYS/99/01 and of the Office of Naval Research. Address correspondence to C. Carboni, College of Science, Physics, Sultan Qaboos University, PO Box 36, Al-Khod 123, Sultanate of Oman.
PY - 2004
Y1 - 2004
N2 - Monomesogen low molar mass organosiloxane liquid-crystal molecules consist of a single mesogenic moiety attached via an alkyl chain to a short siloxane moiety. When the material is cooled from the isotropic phase, the siloxane moieties micro-separate from the mesogenic moieties and aggregate in planes that acts as an effective polymer backbone. The material is therefore in a smectic phase with alternating siloxane-rich layers and mesogen-rich layers. With a suitable design of the mesogenic moiety one can achieve a certain degree of decoupling between the mesogenic-rich layers. Such materials can be expected to display de Vries smectic A phases. In this paper we present monomesogen low molar mass organosiloxane liquid-crystal materials that display a wide temperature range de Vries smectic A* phase. The field dependence of the electric field-induced tilt of the optic axis and the field dependence of the birefringence have been measured at several temperatures. One of the materials displays a transition from de Vries smectic A* to smectic C* at low temperatures.
AB - Monomesogen low molar mass organosiloxane liquid-crystal molecules consist of a single mesogenic moiety attached via an alkyl chain to a short siloxane moiety. When the material is cooled from the isotropic phase, the siloxane moieties micro-separate from the mesogenic moieties and aggregate in planes that acts as an effective polymer backbone. The material is therefore in a smectic phase with alternating siloxane-rich layers and mesogen-rich layers. With a suitable design of the mesogenic moiety one can achieve a certain degree of decoupling between the mesogenic-rich layers. Such materials can be expected to display de Vries smectic A phases. In this paper we present monomesogen low molar mass organosiloxane liquid-crystal materials that display a wide temperature range de Vries smectic A* phase. The field dependence of the electric field-induced tilt of the optic axis and the field dependence of the birefringence have been measured at several temperatures. One of the materials displays a transition from de Vries smectic A* to smectic C* at low temperatures.
UR - http://www.scopus.com/inward/record.url?scp=12844286958&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=12844286958&partnerID=8YFLogxK
U2 - 10.1080/15421400490434937
DO - 10.1080/15421400490434937
M3 - Conference article
AN - SCOPUS:12844286958
SN - 0026-8941
VL - 410
SP - 61/[589]-69/[597]
JO - Molecular Crystals and Liquid Crystals
JF - Molecular Crystals and Liquid Crystals
T2 - Proceedings of the 19th International Liquid Crystal Conference, ILCC2002
Y2 - 30 June 2002 through 5 July 2002
ER -