Study of optical conoscopy in uniaxial and biaxial nematic lyotropic phases

被引：11
作者：
Santos, O. R. [1 ,2 ]
Braga, W. S. [1 ,2 ]
Luders, D. D. [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 | 2014年 / 197卷
关键词：
Uniaxial nematic; Positive biaxial nematic; Negative biaxial nematic; Induced biaxial nematic; LIQUID-CRYSTAL; TRANSITIONS; IMAGE; MIXTURES;
D O I：
10.1016/j.molliq.2014.05.005
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 calamitic nematic (N-C)-biaxial nematic (N-B)-discotic nematic (N-D) phase transitions are studied in a potassium laurate-decanol-potassium sulfate and water mixture by optical conoscopy. The N-C(-)(N-D(+)) phase is uniaxially negative (positive) as expected. A biaxial negative (N-B(-)) nematic phase is optically characterized and confirmed through conoscopic image, inside the biaxial range, beyond the known biaxial positive (N-B(+)) nematic phase. Conoscopic image of a biaxial nematic induced by material flow from N-D(+) phase is investigated and discussed in this work. (C) 2014 Elsevier B.V. All rights reserved.
引用
收藏
页码：120 / 123
页数：4
相关论文
共 30 条
  • [1] Effect of alkyl chain length of alcohols on nematic uniaxial-to-biaxial phase transitions in a potassium laurate/alcohol/K2SO4/water lyotropic mixture
    Akpinar, Erol
    Reis, Dennys
    Figueiredo Neto, Antonio Martins
    [J]. LIQUID CRYSTALS, 2012, 39 (07) : 881 - 888
  • [2] Micelles forming biaxial lyotropic nematic phases
    Amaral, L. Q.
    [J]. LIQUID CRYSTALS, 2010, 37 (6-7) : 627 - 640
  • [3] Measurements of optical anisotropy of a calamitic lyotropic liquid crystal
    Beica, T
    Moldovan, R
    Tintaru, M
    Enache, I
    Frunza, S
    [J]. CRYSTAL RESEARCH AND TECHNOLOGY, 2004, 39 (02) : 151 - 156
  • [4] 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.
    [J]. JOURNAL OF MOLECULAR LIQUIDS, 2013, 187 : 20 - 23
  • [5] An optical conoscopy study of a reentrant discotic nematic-Biaxial nematic phase transition
    Braga, W. S.
    Santos, O. R.
    Sampaio, A. R.
    Kimura, N. M.
    Simoes, M.
    Palangana, A. J.
    [J]. JOURNAL OF MOLECULAR LIQUIDS, 2012, 170 : 72 - 75
  • [6] Image processing as a tool for phase transitions identification
    Eccher, J.
    Sampaio, A. R.
    Viscovini, R. C.
    Conte, G.
    Westphal, E.
    Gallardo, H.
    Bechtold, I. H.
    [J]. JOURNAL OF MOLECULAR LIQUIDS, 2010, 153 (2-3) : 162 - 166
  • [7] ELASTIC CONTINUUM THEORY OF BIAXIAL NEMATICS
    GOVERS, E
    VERTOGEN, G
    [J]. PHYSICAL REVIEW A, 1984, 30 (04): : 1998 - 2000
  • [8] HENDRIKX Y, 1983, J PHYS CHEM-US, V87, P3991, DOI 10.1021/j100243a039
  • [9] Kazanci N., 2003, MAT RES B, V1003
  • [10] Molecular reorientation of a nematic liquid crystal by thermal expansion
    Kim, Young-Ki
    Senyuk, Bohdan
    Lavrentovich, Oleg D.
    [J]. NATURE COMMUNICATIONS, 2012, 3
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