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

Citation
M. Duan et al., 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, LIQ CRYST, 27(9), 2000, pp. 1195-1205
Citations number
36
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physical Chemistry/Chemical Physics
Journal title
LIQUID CRYSTALS
ISSN journal
0267-8292 → ACNP
Volume
27
Issue
9
Year of publication
2000
Pages
1195 - 1205
Database
ISI
SICI code
0267-8292(200009)27:9<1195:LCPODM>2.0.ZU;2-6
Abstract
This paper describes the effect of substituent and ester linkage on smectic properties for some derivatives of 4-R-phenyl 4-(4-octyloxybenzoyloxy)benz oates (1), 4-octyloxyphenyl 4-(4-R-benzyloxy)benzoates (2), 4-(4-octyloxybe nzoyloxy)phenyl 4-R-benzoates (3), and 4-R-phenyl 4-octyloxyphenyl terephth alates (4) where R = OCH3, CH3, OC8H17, C8H17, halogens, CF3, OCF3, CN, NO2 , etc. The thermal properties are discussed in terms of the electrostatic n ature of the substituents and the relative orientation of the ester groups with respect to both terminal substituents. The substituent effect on the l ayer structure of the smectic A phase is also examined by means of a small angle X-ray analysis.