Synthesis and helical supramolecular organization of discotic liquid crystalline dibenzo[hi,st]ovalene

Peripheral and non-peripheral tetra(13,17-dioxanonacosane-15-hydroxy) substituted metal free-, Ni (II) and Zn (II) phthalocyanines have been synthesized from the corresponding phthalonitrile derivatives in the presence of the anhydrous metal salt ( NiCl 2 and Zn ( OOCCH 3)2) or a strong organic base. The new compounds have been characterised by elemental analyses, IR, NMR, mass spectra and electronic spectroscopy. The mesogenic properties of these new materials were studied by differential scanning calorimetry (DSC), optical polarised microscopy and X-ray investigations. The effects of peripheral or non-peripheral substitution of (13,17-dioxanonacosane-15-hydroxy) to the phthalocyanine ring are also investigated. It is found out that non-peripheral substituted phthalocyanine derivatives (4a-c) are liquid at room temperature whereas, peripheral substituted phthalocyanine derivatives (7a-c) exhibit ordered discotic hexagonal columnar mesophases ( Col h) at room temperature.

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Bicontinuous Cubic and Hexagonal Columnar Liquid Crystalline Ion-Conductors at Room Temperature in Ion-Doped Dendritic Amphiphiles

Crystals ◽

10.3390/cryst10030193 ◽

2020 ◽

Vol 10 (3) ◽

pp. 193

Author(s):

Thi Huyen Do ◽

Ho-Joong Kim ◽

Manh Linh Nguyen ◽

Byoung-Ki Cho

Keyword(s):

Liquid Crystalline ◽

Room Temperature ◽

Molecular Design ◽

Three Dimensional ◽

Impedance Analysis ◽

Practical Applications ◽

Alkyl Chains ◽

Bicontinuous Cubic ◽

Hexagonal Columnar ◽

Ion Conductors

A bicontinuous cubic (Cubbi) liquid crystalline (LC) phase consisting of three dimensional (3D) conducting networks is a promising structural platform for ion-conductors. For practical applications using this fascinating LC structure, it is necessary to suppress crystallization at room temperature (RT). Herein, we report the Cubbi structure at RT and the morphology–dependent conduction behavior in ionic samples of a non-crystallizable dendritic amphiphile. In the molecular design, branched alkyl chains were used as an ionophobic part instead of crystallizable linear alkyl chains. Two ionic samples with Cubbi and hexagonal columnar (Colhex) LC phases at RT were prepared by adding different amounts of lithium salt to the amphiphile. Impedance analysis demonstrated that the Cubbi phase contributed to the faster ion-conduction to a larger extent than the Colhex phase due to the 3D ionic networks of the Cubbi phase. In addition, the temperature–dependent impedance and electric modulus data provided information regarding the phase transition from microphase-separated phase to molecularly mixed liquid phase.

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Room-temperature discotic liquid-crystalline coronene diimides exhibiting high charge-carrier mobility in air

Journal of Materials Chemistry ◽

10.1039/b910898j ◽

2009 ◽

Vol 19 (37) ◽

pp. 6688 ◽

Cited By ~ 88

Author(s):

Zesheng An ◽

Junsheng Yu ◽

Benoit Domercq ◽

Simon C. Jones ◽

Stephen Barlow ◽

...

Keyword(s):

Charge Carrier ◽

Carrier Mobility ◽

Liquid Crystalline ◽

Room Temperature ◽

Charge Carrier Mobility ◽

High Charge ◽

High Charge Carrier Mobility

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Self-Assembly-Induced Supramolecular Hexagonal Columnar Liquid Crystalline Phase Using Laterally Attached Nonmesogenic Templates

Macromolecules ◽

10.1021/ma991768a ◽

2000 ◽

Vol 33 (17) ◽

pp. 6315-6320 ◽

Cited By ~ 42

Author(s):

Huilin Tu ◽

Xinhua Wan ◽

Yuxiang Liu ◽

Xiaofang Chen ◽

Dong Zhang ◽

...

Keyword(s):

Crystalline Phase ◽

Self Assembly ◽

Liquid Crystalline ◽

Liquid Crystalline Phase ◽

Hexagonal Columnar

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Temperature-Dependent X-Ray Studies of Discotic Hexagonal Columnar Mesophases in Trinuclear Gold(I) Pyrazolate Complex

Malaysian Journal of Fundamental and Applied Sciences ◽

10.11113/mjfas.v17n3.2112 ◽

2021 ◽

Vol 17 (3) ◽

pp. 285-294

Author(s):

Mohamad Azani Abd Khadir Jalani ◽

Hendrik O. Lintang ◽

Siew Ling Lee ◽

Juan Matmin ◽

Nur Fatiha Ghazalli ◽

...

Keyword(s):

Liquid Crystals ◽

Liquid Crystalline ◽

Variable Temperature ◽

Gold Complex ◽

Scanning Calorimetry ◽

X Ray ◽

Heating And Cooling ◽

Depth Study ◽

Columnar Mesophases ◽

Hexagonal Columnar

Gold(I) pyrazolate complex ([Au3Pz3]C10TEG) has been widely studied due to its interesting liquid crystalline properties by exhibiting the discotic hexagonal columnar arrangement. Generally, the liquid crystalline properties of the gold complex were confirmed based on their differential scanning calorimetry thermogram and polarized optical microscopy (POM) images. However, there is still no in-depth study on the phase transition in liquid crystals of [Au3Pz3]C10TEG especially on its structural change at variable temperature. In this study, the resulting liquid crystalline properties of [Au3Pz3]C10TEG upon being heated and cooled was extensively demonstrated via variable-temperature POM (VT-POM) and small angle X-ray scattering (VT-SAXS). Based on the VT-POM images, it was indicated that [Au3Pz3]C10TEG displayed a fan-shaped texture for typical arrangements of discotic hexagonal columnar of liquid crystals. Moreover, VT-SAXS results was in good agreement with the VT-POM images as it showed that [Au3Pz3]C10TEG might consist of two types of stacking system, which are ordered and disordered hexagonal discotic arrangements. Likewise, VT-SAXS analysis also demonstrated that hexagonal columnar mesophase of [Au3Pz3]C10TEG could be recovered even after the heating and cooling for two cycles.

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Influence of molecular structure on helicoidal structure and NMR spectra of chiral liquid crystalline esters

Bulletin of the Military University of Technology ◽

10.5604/01.3001.0010.1887 ◽

2017 ◽

Vol 66 (2) ◽

pp. 25-35

Author(s):

Anna Drzewicz ◽

Marzena Tykarska ◽

Mateusz Szala ◽

Magdalena Żurowska

Keyword(s):

Molecular Structure ◽

Nmr Spectra ◽

Liquid Crystalline ◽

Room Temperature ◽

Alkyl Chain ◽

Light Reflection ◽

13C Nmr Spectra ◽

1H And 13C Nmr ◽

Antiferroelectric Phase ◽

Helicoidal Structure

Three-ring chiral liquid crystalline compounds, forming antiferroelectric phase, differing in the structure of alkyl chain and in the substitution of benzene ring by fluorine atoms were studied. The measurements of helical pitch, based on the selective light reflection phenomenon, were performed as well as 1H and 13C NMR spectra at room temperature were registered. The influence of molecular structure as well as the type of helicoidal structure on the chemical shift of signals coming from chiral center was observed. Keywords: liquid crystals, helicoidal structure, nuclear magnetic resonance, antiferroelectric phase

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Uv Curable Liquid Crystals and Their Application

MRS Proceedings ◽

10.1557/proc-425-293 ◽

1996 ◽

Vol 425 ◽

Author(s):

H. Takatsu ◽

H. Hasebe

Keyword(s):

Liquid Crystals ◽

Light Scattering ◽

Liquid Crystalline ◽

Room Temperature ◽

Polymer Network ◽

Driving Voltage ◽

Uv Curable ◽

Good Thermal Stability ◽

Photo Polymerization ◽

Smectic A

AbstractSome classes of liquid crystalline monoacrylates having no methylene spacers in a side chain have been prepared. The liquid crystalline monoacrylates have effects to reduce the driving voltage and the hysteresis for a light scattering display of Polymer Network liquid crystals prepared by photo-polymerization-induced phase separation.By photo-polymerization of a chiral monoacrylate monomer in a nematic liquid crystalline host including a black dichroic dye, a polarizer free reflective Spiral Polymer Aligned Nematic (SPAN) Guest Host (GH) LCD exhibiting a low driving voltage has been fabricated. The effect of the spiral polymers made of some kinds of chiral monoacrylates for a Super Twisted Nematic (STN) LCD using SPAN liquid crystals is discussed.UV-curable liquid crystals showing nematic phases at room temperature have been developed. By in situ photo-polymerization, the UV-curable liquid crystals can be utilized for the retardation film with high quality and good thermal stability. The fabrication of various kinds of retardation film using the UV-curable liquid crystals is discussed.UV-curable liquid crystals having isotropic-nematic-smectic A phase sequence have been developed and the photo-polymerization at the state of their uniaxially oriented smectic A phases at room temperature is discussed. The polymerized film is optically uniaxial and transparent without light scattering.

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Discotic Liquid Crystals Based on Cu(I) Complexes with Benzoylthiourea Derivatives Containing a Perfluoroalkyl Chain

Journal of Chemistry ◽

10.1155/2018/7943763 ◽

2018 ◽

Vol 2018 ◽

pp. 1-10

Author(s):

Monica Iliş ◽

Viorel Cîrcu

Keyword(s):

Liquid Crystalline ◽

Large Temperature ◽

Discotic Liquid Crystals ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Polarized Optical Microscopy ◽

X Ray ◽

Ir And Nmr Spectroscopy ◽

Hexagonal Columnar ◽

Mesomorphic Properties

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.

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