Zustandsdiagramme und röntgenographische Untersuchungen einiger induzierter smektischer Mischphasen / Phase Diagrams and X -R ay Studies of the Induced Smectic Phases of Liquid Crystal Mixtures

Phase diagrams of mixtures of terminal polar and terminal non-polar liquid crystals that exhibit smectic phases with very large ranges of stability are presented. X-ray studies show that the induced phases are of type SA, SB or SE. The determination of the layer thickness shows that the induced smectic phases are composed of monolayers, whereas the terminal polar components are composed of bilayers. A model for the formation of the induced smectic phases is proposed.

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Direct Determination of the Anisotropy of the Magnetic Susceptibility in Smectic Liquid Crystals

Zeitschrift für Naturforschung A ◽

10.1515/zna-1985-0110 ◽

1985 ◽

Vol 40 (1) ◽

pp. 46-51 ◽

Cited By ~ 3

Author(s):

G. Illian ◽

H. Kneppe ◽

F. Schneider

Keyword(s):

Magnetic Susceptibility ◽

Liquid Crystal ◽

Liquid Crystals ◽

Direct Determination ◽

Oscillation Period ◽

Smectic Liquid Crystals ◽

Smectic Liquid Crystal ◽

Smectic Phases ◽

Phase Sequence

A sample of an aligned smectic liquid crystal, suspended in a magnetic field, can be excited to oscillations. Measurement of the oscillation period allows a direct determination of the anisotropy of the magnetic susceptibility. Liquid crystals exhibiting the phase sequence isotropicnematic- smectic A can be aligned very well and precise y.A values can be determined. A direct transformation from the isotropic to the smectic phase or phase transitions between smectic phases can cause an incomplete alignment of the liquid crystal and worse results.

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Proton spin relaxation study of polar liquid crystals with induced smectic phases

10.1117/12.299980 ◽

1998 ◽

Cited By ~ 1

Author(s):

V. Satheesh ◽

D. Loganathan ◽

K. Venu ◽

V. S. S. Sastry ◽

Roman S. Dabrowski ◽

...

Keyword(s):

Liquid Crystals ◽

Spin Relaxation ◽

Proton Spin ◽

Polar Liquid ◽

Smectic Phases ◽

Relaxation Study ◽

Induced Smectic Phases

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Induced smectic phases in phase diagrams of binary nematic liquid crystal mixtures

The Journal of Chemical Physics ◽

10.1063/1.3567100 ◽

2011 ◽

Vol 134 (12) ◽

pp. 124508 ◽

Cited By ~ 4

Author(s):

Tsang-Min Huang ◽

Kathleen McCreary ◽

Shila Garg ◽

Thein Kyu

Keyword(s):

Liquid Crystal ◽

Phase Diagrams ◽

Nematic Liquid Crystal ◽

Smectic Phases ◽

Induced Smectic Phases

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Induced Smectic Phases II. Influence of the Amino Substituent on the Induction of Smectic Phases

Zeitschrift für Naturforschung A ◽

10.1515/zna-1981-1011 ◽

1981 ◽

Vol 36 (10) ◽

pp. 1086-1091 ◽

Cited By ~ 1

Author(s):

F. Schneider ◽

N. K. Sharma

Keyword(s):

Liquid Crystal ◽

Electron Donor ◽

Amino Group ◽

Donor Property ◽

Smectic Phases ◽

Ct Complexes ◽

Induced Smectic Phases

The diagrams of state have been studied for some liquid crystal mixtures which show the induction of smectic phases. Each of the systems studied contains one component with an amino group which influences the polarity and the electron donor property of the molecules. The discussion of the diagrams of state, of the thickness of the smectic layers and of the colours of the mixtures, which indicate the formation of CT complexes, shows that existing models can not explain the induction of smectic phases.

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Optical Kossel Lines and Fluorescence in Photonic Liquid Crystals

Crystals ◽

10.3390/cryst10060541 ◽

2020 ◽

Vol 10 (6) ◽

pp. 541

Author(s):

Vladimir A. Belyakov

Keyword(s):

Experimental Data ◽

Liquid Crystal ◽

Liquid Crystals ◽

Light Absorption ◽

Fluorescence Polarization ◽

Direct Connection ◽

X Ray ◽

Optical Analog ◽

Theoretical Results ◽

Observation Results

We propose a general analytical way to describe the fluorescence peculiarities in photonic liquid crystals (revealing themselves as an optical analog of the X-ray Kossel lines in conventional crystals) based at the localized optical edge modes existing in perfect photonic liquid crystal layers. The proposed approach allows us to predict theoretically the properties of optical Kossel lines in photonic liquid crystal (fluorescence polarization, spectral and angular fluorescence distribution, influence of the light absorption in liquid crystal, and, in particular, existing the optical Borrmann effect if the absorption in liquid crystal is locally anisotropic). Comparison of the theoretical results and the known experimental data shows that the theory reproduces sufficiently well the observation results on the fluorescence in photonic liquid crystals. For confirming a direct connection of the optical Kossel lines to the localized optical edge modes in perfect photonic liquid crystal, we propose the application of time-delayed techniques in studying the optical Kossel lines.

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New liquid crystal formation induced by nanoscale phase separation composed of bent-core liquid crystal and rod-like cholesteric liquid crystal mixtures

Soft Matter ◽

10.1039/d0sm01748e ◽

2021 ◽

Author(s):

Yoichi Takanishi

Keyword(s):

Liquid Crystal ◽

Phase Separation ◽

Liquid Crystals ◽

Small Angle ◽

Cholesteric Liquid Crystal ◽

Crystal Formation ◽

Nano Structure ◽

X Ray ◽

Nanoscale Phase Separation ◽

X Ray Scattering

Herein, the local nano-structure in mixtures of cholesteric liquid crystals and a bent-core molecule was analyzed via the small-angle X-ray scattering.

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