DOI: 10.1051/jp2:1994152
J. Phys. II France 4 (1994) 627-643
Novel sequence with incommensurate SA phases in a new dimesogenic liquid crystal
F. Hardouin1, M. F. Achard1, Jung-Il Jin2, Jin-Wook Shin2 and Yong-Kuk Yun21 Centre de Recherche Paul Pascal, Université Bordeaux I, Av. A. Schweitzer, 33600 Pessac, France
2 Department of Chemistry, College of Sciences, Korea University, Seoul 136-701, Korea
(Received 16 November 1993, accepted in final form 10 January 1994)
Abstract
We present differential scanning calorimetry, optical and X-ray diffraction measurements
for a new dimesogenic liquid crystal compound (KI5). The rich polymorphism of this compound
includes new smectic phases and rare phase transitions. In particular the first observation in a
pure compound of two incommensurate SA phases as well as cholesteric and helical smectic phases
(TGB and SC
* phases) are reported. We discuss this observation in terms of the dual peculiar
structural character of the molecule : a polyphilic and dimesogenic system including the concept
of the central flexible spacer.
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