Conoscopic image of a biaxial negative nematic phase in a potassium laurate-decanol-D2O mixture

被引:23
作者
Braga, W. S. [1 ,2 ]
Santos, O. R. [1 ,2 ]
Luders, D. D. [1 ]
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
关键词
Conoscopic image; Discotic nematic; Biaxial positive nematic; Biaxial negative nematic; Calamitic nematic; TRANSITIONS; TEMPERATURE;
D O I
10.1016/j.molliq.2013.05.002
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
The discotic nematic (N-D)-biaxial nematic (N-B)-calamitic nematic (N-C) phase transitions are studied in a potassium laurate-decanol-D2O mixture by optical conoscopy. The N-D(+) (N-C(-)) phase is uniaxial positive (negative) as expected. Nevertheless, inside the biaxial range, beyond the known biaxial positive (N-B(+)) nematic phase we have also found a biaxial negative (N-B(-)) nematic phase optically characterized through conoscopic images. A transition point from a N-B(+) to a N-B(-) configuration is determined and discussed in this work. (C) 2013 Elsevier B.V. All rights reserved.
引用
收藏
页码:20 / 23
页数:4
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