In this article we present an investigation of the liquid crystal properties of nonchiral and racemic branched alkyl chain (swallow-tailed) molecules and some chiral analogues based on a cinnamic acid core group, It was found in these systems that increasing the extent of the branching of the terminal alkyl chain increased the incidence of alternating tilt smectic phases, whereas smectic C-alpha and smectic C-gamma phases were suppressed. X-ray studies of the effect on the layer spacing in the smectic A phase of increasing the long alkyl branch of one series of compounds are included. Results of polarisation studies on some chiral analogues are also reported.
Mesomorphism dependence on central bridge and tail ended polar group
作者:Avani R. Ranchchh、Kavita Chavda、Roshani Bhanderi、Suman Patel、U. C. Bhoya
DOI:10.1080/15421406.2018.1499595
日期:2018.4.13
A novel azoester homologous series of laterally and terminally substituted viz, RO-C6H4-CH=CH-COO-C6H3-(CH3) -N=N-C6H4-Cl is synthesized, characterized and studied with a view to understand and establish the relation between molecular structure and thermotropic liquid crystalline property of its homologs. Series consists of twelve homologs. LC properties commence from very first member of a series and continue up to last homolog as enantiotropic nematic with absence of smectic property even in the monotropic condition. Transition temperatures of homologs were determined by polarizing optical microscopy equipped with a heating stage. The transition curves Cr?N and N?I behaved in normal manner. Thermal stability for nematic is 196.7 degrees C whose mesophaselength ranges from 35 degrees C to 131 degrees C.
Inui, S.; Suzuki, T.; Iimura, N., Molecular Crystals and Liquid Crystals Science and Technology, Section A: Molecular Crystals and Liquid Crystals, 1994, vol. 239, p. 1 - 10
作者:Inui, S.、Suzuki, T.、Iimura, N.、Iwane, H.、Nohira, H.
作者:R. P. Tuffin、J. W. Goodby、D. Bennemann、G. Heppke、D. Lötzsch、G. Scherowsky
DOI:10.1080/10587259508038683
日期:1995.2
In this article we present an investigation of the liquid crystal properties of nonchiral and racemic branched alkyl chain (swallow-tailed) molecules and some chiral analogues based on a cinnamic acid core group, It was found in these systems that increasing the extent of the branching of the terminal alkyl chain increased the incidence of alternating tilt smectic phases, whereas smectic C-alpha and smectic C-gamma phases were suppressed. X-ray studies of the effect on the layer spacing in the smectic A phase of increasing the long alkyl branch of one series of compounds are included. Results of polarisation studies on some chiral analogues are also reported.