Refractive index measurements in a reentrant discotic nematic-biaxial nematic phase transition

被引：5
作者：
Braga, W. S. [1 ,2 ]
Luders, D. D. [1 ,3 ]
Santos, O. R. [1 ,2 ]
Sampaio, A. R. [1 ]
Kimura, N. M. [1 ]
Simoes, M. [4 ]
Palangana, A. J. [1 ]
机构：
[1] Univ Estadual Maringa, Dept Fis, Maringa, Parana, Brazil
[2] Univ Tecnol Fed Parana, Campo Maurao, Brazil
[3] Univ Estadual Maringa, Dept Engn Agr, Cidade Gaucha, Brazil
[4] Univ Estadual Londrina, Dept Fis, Londrina, Brazil
来源：
PHASE TRANSITIONS | 2018年 / 91卷 / 08期
关键词：
Reentrant discotic; Refractive indices; Optical birefringence; Optical conoscopic; LYOTROPIC LIQUID-CRYSTAL; OPTICAL MICROSCOPY; ORDER-PARAMETER; BEHAVIOR; MIXTURE; IMAGE; CONOSCOPY;
D O I：
10.1080/01411594.2018.1506124
中图分类号：
O7 [晶体学];
学科分类号：
0702 ; 070205 ; 0703 ; 080501 ;
摘要：
The optical characterization of uniaxial (reentrant discotic - N-Dr and discotic - N-D) and biaxial nematic (N-B) phases requires the measurements of two and three refractive indices, respectively. These optical parameters were determined near the reentrant isotropic (I-r) - N-Dr - N-B - N-D-isotropic (I) phase transitions in a lyotropic mixture of potassium laurate, decanol and D2O. Biaxial positive (N-B) nematic phase is optically characterized between two uniaxial discotic nematic phases from refractive index data and confirmed via conoscopic images. The micellar configuration of uniaxial and biaxial nematic phases is discussed as a consequence of our experimental data.
引用
收藏
页码：833 / 839
页数：7
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