An optical conoscopy study of a reentrant discotic nematic-Biaxial nematic phase transition

被引：23

作者：

Braga, W. S. ^{[1
,2
]}

Santos, O. R. ^{[1
,2
]}

Sampaio, A. R. ^{[1
]}

Kimura, N. M. ^{[1
]}

Simoes, M. ^{[3
]}

Palangana, A. J. ^{[1
]}

机构：

[1] Univ Estadual Maringa, Dept Fis, BR-87020900 Maringa, Parana, Brazil

[2] Univ Tecnol Fed Parana, BR-87301006 Campo Mourao, Parana, Brazil

[3] Univ Estadual Londrina, Dept Fis, BR-86051990 Londrina, PR, Brazil

来源：

JOURNAL OF MOLECULAR LIQUIDS | 2012年 / 170卷

关键词：

Discotic nematic; Biaxial nematic; Optical conoscopy; LYOTROPIC LIQUID-CRYSTAL; ORDER-PARAMETER; TEMPERATURE; MIXTURES; ANISOTROPY;

D O I：

10.1016/j.molliq.2012.03.007

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

A fundamental phase diagram with lyotropic nematic liquid crystals was reported by Yu and Saupe a long time ago. Two uniaxial (calamitic-N-C and discotic-N-D) and one biaxial nematic (N-B) phases were determined by these authors. The phase diagram also predicted the existence of the N-D-N-B-N-D phase transitions. Along the years, this phase diagram has been studied by several authors and yet these phase transitions have not been observed. In this work, we present a study of this phase sequence through optical conoscopy. The occurrence of these phase transitions is here investigated and optically characterized through conoscopic image. (C) 2012 Elsevier B.V. All rights reserved.

引用

页码：72 / 75

页数：4

共 50 条

[41] Nematic-isotropic phase transition in turbulent thermal convection
Weiss, Stephan
Ahlers, Guenter
JOURNAL OF FLUID MECHANICS, 2013, 737 : 308 - 328
[42] Conoscopic image of a biaxial negative nematic phase in a potassium laurate-decanol-D2O mixture
Braga, W. S.
Santos, O. R.
Luders, D. D.
Sampaio, A. R.
Kimura, N. M.
Simoes, M.
Palangana, A. J.
JOURNAL OF MOLECULAR LIQUIDS, 2013, 187 : 20 - 23
[43] Effect of head-group size of some tetradecylalkylammonium bromide surfactants on obtaining the lyotropic biaxial nematic phase
Akpinar, Erol
Guner, Emre
Demir-Ordu, Oznur
Figueiredo Neto, Antonio Martins
EUROPEAN PHYSICAL JOURNAL E, 2019, 42 (04):
[44] Refractive index, density and order parameter of two binary mixtures showing reentrant nematic phase
Giri, SK
Pradhan, NK
Paul, R
Paul, S
Mandal, P
Dabrowski, R
Brodzik, M
Czuprynski, K
MOLECULAR CRYSTALS AND LIQUID CRYSTALS SCIENCE AND TECHNOLOGY SECTION A-MOLECULAR CRYSTALS AND LIQUID CRYSTALS, 1999, 330 : 1357 - 1364
[45] Critical behavior of optical birefringence at the nematic-smectic A phase transition in a binary liquid crystal system
Sarkar, Sudipta Kumar
Das, Malay Kumar
JOURNAL OF MOLECULAR LIQUIDS, 2014, 199 : 415 - 418
[46] Refractive and birefringent properties and order parameter of nematic liquid crystal at the direct and reverse nematic ⇆ isotropic liquid phase transition
Mamuk, A. E.
Nesrullajev, A.
JOURNAL OF OPTOELECTRONICS AND ADVANCED MATERIALS, 2016, 18 (11-12): : 928 - 937
[47] Investigation of the interaction of alkali ions with surfactant head groups for the formation of lyotropic biaxial nematic phase via optical birefringence measurements
Akpinar, Erol
Reis, Dennys
Figueiredo Neto, Antonio Martins
EMERGING LIQUID CRYSTAL TECHNOLOGIES VIII, 2013, 8642
[48] Signatures of a Quantum Griffiths Phase Close to an Electronic Nematic Quantum Phase Transition
Reiss, Pascal
Graf, David
Haghighirad, Amir A.
Vojta, Thomas
Coldea, Amalia, I
PHYSICAL REVIEW LETTERS, 2021, 127 (24)
[49] Effect of Molecular Flexibility on the Nematic-to-Isotropic Phase Transition for Highly Biaxial Molecular Non-Symmetric Liquid Crystal Dimers
Sebastian, Nerea
Orencio Lopez, David
Diez-Berart, Sergio
Rosario de la Fuente, Maria
Salud, Josep
Angel Perez-Jubindo, Miguel
Blanca Ros, Maria
MATERIALS, 2011, 4 (10): : 1632 - 1647
[50] Numerical Study of the Isotropic-Nematic Phase Transition in Liquid Crystals using the String Method
Li, Yunzhi
Ren, Weiqing
COMMUNICATIONS IN COMPUTATIONAL PHYSICS, 2018, 23 (05) : 1534 - 1548

← 1 2 3 4 5 →