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
收藏
页码：72 / 75
页数：4
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