Jpn. J. Appl. Phys. 29 (1990) pp. 131-137 |Next Article| |Table of Contents|
|Full Text PDF (1630K)| |Buy This Article|
Molecular Orientational Structures in Ferroelectric, Ferrielectric and Antiferroelectric Smectic Liquid Crystal Phases as Studied by Conoscope Observation
Tokyo Institute of Technology, Department of Organic and Polymeric Materials
(Received September 27, 1989; accepted for publication November 18, 1989)
Molecular orientational structures in MHPOBC were studied by means of conoscope observation. Contrary to a ferroelectric response of the conoscope to an electric field in the smectic C* phase, the conoscopic figure in the antiferroelectric smectic CA* phase does not shift its center and is biaxial with its optic plane perpendicular to the field direction. This conoscope change is only due to a dielectric contribution, indicating the existence of the inherent threshold in the electric field induced transition to the ferroelectric phase. In between the ferroelectric and antiferroelectric phases, a kind of ferrielectric phase was clearly distinguished in the field response of the conoscopic figure; the shift of the conoscope center perpendicular to the applied field and the biaxial optic plane parallel to the field suggest a novel molecular orientational structure.
KEYWORDS:ferroelectric liquid crystal, antiferroelectric, ferrielectric, smectic liquid crystal, conoscope, biaxiality
- A. D. L. Chandani, Y. Ouchi, H. Takezoe, A. Fukuda, K. Terashima, K. Furukawa and A. Kishi:
Jpn. J. Appl. Phys. 28 (1989) L1261[JSAP].
- A. D. L. Chandani, E. Gorecka, Y. Ouchi, H. Takezoe and A. Fukuda:
Jpn. J. Appl. Phys. 28 (1989) L1265[JSAP].
- H. Takezoe, J. Lee, A. D. L. Chandani, E. Gorecka, Y. Ouchi, A. Fukuda, K. Terashima and K. Furukawa: to be published in Ferroelectrics (Proceedings of the 2nd Ferroelectric Liquid Crystal Symposium, Göteborg, 1989).
- A. D. L. Chandani, T. Hagiwara, Y. Suzuki, Y. Ouchi, H. Takezoe and A. Fukuda:
Jpn. J. Appl. Phys. 27 (1988) L729[JSAP].
- K. Furukawa, K. Terashima, M. Ichihashi, S. Saitoh, K. Miyazawa and T. Inukai: Ferroelectrics 85 (1988) 451.
- Y. Suzuki, T. Hagiwara, I. Kawamura, N. Okamura, T. Kitazume, M. Kakimoto, Y. Imai, Y. Ouchi, H. Takezoe and A. Fukuda: Liq. Cryst. 6 (1989) 167.
- M. Johno, A. D. L. Chandani, Y. Ouchi, H. Takezoe, A. Fukuda, M. Ichihashi and K. Furukawa:
Jpn. J. Appl. Phys. 28 (1989) L119[JSAP].
- M. Johno, Y. Ouchi, H. Takezoe, A. Fukuda, K. Terashima and K. Furukawa:
Jpn. J. Appl. Phys. 29 (1990) L111[JSAP].
- M. Fukui, H. Orihara, Y. Yamada, N. Yamamoto and Y. Ishibashi:
Jpn. J. Appl. Phys. 28 (1989) L849[JSAP].
- Y. Ouchi, T. Shingu, H. Takezoe, A. Fukuda, E. Kuze, M. Koga and N. Goto:
Jpn. J. Appl. Phys. 23 (1984) L660[JSAP].
- M. Born and E. Wolf: Principles of Optics (Pergamon Press, 1970) 4th ed., p. 701.
- E. E. Wahlstrom: Optical Crystallography (John Wiley and Sons, 1979) 5th ed., p. 275.
- Y. Galerne: J. Phys. (France) 39 (1978) 1311.
- M. Yamashita and H. Kimura: J. Phys. Soc. Jpn. 52 (1983) 333.
- M. Nakagawa: Liq. Cryst. 3 (1988) 573.
- K. Hiraoka, A. Taguchi, Y. Ouchi, H. Takezoe and A. Fukuda:
Jpn. J. Appl. Phys. 29 (1990) L103[JSAP].