Liquid crystalline properties of dissymmetric molecules IV. The substituent effect on thermal properties of nematic and smectic A phases in three aromatic ring systems with ester linkages |
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Authors: | Meili Duan Takeyasu Tasaka Hiroaki Okamoto Vladimir F Petrov Shunsuke Takenaka |
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Institution: | Department of Advanced Materials Science and Engineering, Faculty of Engineering, Yamaguchi University, Tokiwadai 2557, Ube, Yamaguchi 755-8611, Japan |
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Abstract: | This paper describes the effect of substituent and ester linkage on smectic properties for some derivatives of 4-R -phenyl 4-(4-octyloxybenzoyloxy)benzoates (1), 4-octyloxyphenyl 4-(4-R-benzyloxy)benzoates (2), 4-(4-octyloxybenzoyloxy)phenyl 4- R -benzoates (3), and 4-R-phenyl 4-octyloxyphenyl terephthalates (4) where R = OCH3, CH3, OC8H17, C8H17, halogens, CF3, OCF3, CN, NO2, etc. The thermal properties are discussed in terms of the electrostatic nature of the substituents and the relative orientation of the ester groups with respect to both terminal substituents. The substituent effect on the layer structure of the smectic A phase is also examined by means of a small angle X-ray analysis. |
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Keywords: | solvatochromism probe cyanobiphenyl liquid crystal matrix anisotropy Kamlet–Abboud–Taft polarity function |
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