Optical and mesomorphic properties characterisation of chiral liquid crystalline copolysiloxane exhibiting cholesteric and blue phases

2013 ◽  
Vol 40 (11) ◽  
pp. 1550-1560 ◽  
Author(s):  
Ji-Wei Wang ◽  
Bao-Yan Zhang
1991 ◽  
Vol 1 (10) ◽  
pp. 1451-1468 ◽  
Author(s):  
H.-R. Trebin ◽  
W. Fink ◽  
H. Stark

2008 ◽  
Vol 18 (13) ◽  
pp. 1504 ◽  
Author(s):  
Stéphane Campidelli ◽  
Marjorie Séverac ◽  
David Scanu ◽  
Robert Deschenaux ◽  
Ester Vázquez ◽  
...  

2019 ◽  
Vol 41 (6) ◽  
pp. 1107-1107
Author(s):  
Mohammed Taha Yaseen and Abdullah Hussein Kshash Mohammed Taha Yaseen and Abdullah Hussein Kshash

The paper presents six homologues series of Schiff bases ether compounds distinguished by the length of terminal alkoxy groups which substituted on a side benzene nucleus. The above structures were demonstrated through the use of spectroscopic techniques, like FT- IR and 1H-NMR. Polarized hot stage optical microscopy was used to study both mesomorphic properties and phase transitions. The results showed that out of the six compounds only three (B2, B3 and B4) were pure (marble) nematic mesophase, while no liquid crystal properties for (B5, B6 and B7) compounds. The theoretical study for the electronic structures was intended to study the effects of alkyl chain length on the electronic structure by using Gaussian program, DFT and 6-31G as basis set. The theoretical results indicate that there is no effect to the terminal substituted alkoxy groups on the HOMO energies but there is an effect on LUMO energies through decreasing energy for the prepared compounds.


2017 ◽  
Vol 26 (3) ◽  
pp. 46-54 ◽  
Author(s):  
Vinay S. Sharma ◽  
Rajesh H. Vekariya ◽  
Anuj S. Sharma ◽  
R. B. Patel

2012 ◽  
Vol 8 ◽  
pp. 371-378 ◽  
Author(s):  
Katharina C Kress ◽  
Martin Kaller ◽  
Kirill V Axenov ◽  
Stefan Tussetschläger ◽  
Sabine Laschat

4-Cyano-1,1'-biphenyl derivatives bearing ω-hydroxyalkyl substituents were reacted with methyl 3-chloro-3-oxopropionate or cyanoacetic acid, giving liquid-crystalline linear malonates and cyanoacetates. These compounds formed monotropic nematic phases at 62 °C down to ambient temperature upon cooling from the isotropic liquid. The mesomorphic properties were investigated by differential scanning calorimetry, polarizing optical microscopy and X-ray diffraction (WAXS).


1992 ◽  
Vol 47 (3) ◽  
pp. 515-520 ◽  
Author(s):  
V. Vill ◽  
J. Thiem ◽  
P. Rollin

Abstract Liquid Crystalline Aromatic Cholesterol Derivates A series of aromatic cholesteryl ethers, esters, phenylcarbonates and benzylcarbonates were prepared and their liquid crystalline properties studied. The occurence of ferroelectric phases as well as properties of cholesteric and blue phases alternate with the number of linking atomes between steroid and atomatic system


2009 ◽  
Vol 82 (3) ◽  
pp. 228-239 ◽  
Author(s):  
Md Lutfor Rahman ◽  
Jahimin Asik ◽  
Sandeep Kumar ◽  
Sidik Silong ◽  
Mohd Zaki Ab Rahman

2018 ◽  
Vol 2018 ◽  
pp. 1-10
Author(s):  
Monica Iliş ◽  
Viorel Cîrcu

Mesomorphic three-coordinate copper(I) complexes ([Cu(BTU)2X], where X = Cl or Br) based on a new N-benzoylthiourea (BTU) ligand with two decyloxy and one perfluorooctyl groups at its periphery were designed and prepared. The BTU ligand coordinates via the S atom in a neutral monodentate fashion as confirmed by IR and NMR spectroscopy data. The liquid crystalline behavior of these copper(I) complexes was investigated by a combination of polarized optical microscopy (POM), differential scanning calorimetry (DSC), and X-ray diffraction analysis (XRD), while their thermal stability was studied by thermogravimetric analysis (TGA). These new copper(I) complexes have mesomorphic properties and exhibit a hexagonal columnar mesophase over a large temperature range, more than 100°C.


2001 ◽  
Vol 12 (2) ◽  
pp. 184-191 ◽  
Author(s):  
Aloir A. Merlo ◽  
Olga M. S. Ritter ◽  
Fabiano V. Pereira ◽  
Carolina H. Vieira ◽  
Nádya P. da Silveira

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