Large Flow Birefringence of Nematogenic Bent-Core Liquid Crystals

被引：45

作者：

Bailey, C. ^{[1
,2
]}

Fodor-Csorba, K. ^{[3
]}

Verduzco, R. ^{[4
]}

Gleeson, J. T. ^{[5
]}

Sprunt, S. ^{[5
]}

Jakli, A. ^{[1
,2
]}

机构：

[1] Kent State Univ, Inst Liquid Crystal, Kent, OH 44242 USA

[2] Kent State Univ, Chem Phys Interdisciplinary Program, Kent, OH 44242 USA

[3] Res Inst Solid State Phys & Opt, Budapest, Hungary

[4] Oak Ridge Natl Lab, Ctr Nanophase Mat Sci, Oak Ridge, TN 37830 USA

[5] Kent State Univ, Dept Phys, Kent, OH 44242 USA

来源：

PHYSICAL REVIEW LETTERS | 2009年 / 103卷 / 23期

关键词：

BANANA-SHAPED MOLECULES; SHEAR-FLOW; VISCOELASTIC SOLUTIONS; TETRAHEDRATIC PHASE; NEMATIC TRANSITION; ACHIRAL MOLECULES; ISOTROPIC-PHASE; COMPLEX; POLYMERS; MESOGENS;

D O I：

10.1103/PhysRevLett.103.237803

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We have found that bent-core liquid crystalline materials show exceptionally large intrinsic flow birefringence in their isotropic liquid phase. This effect is more than 100 times larger than typical values measured for low molecular weight liquid crystals. The specific flow birefringence (i.e., normalized by the flow viscosity) is an order of magnitude larger than in both side-chain polymeric as well as low molecular weight liquid crystals. We propose that this large enhancement for bent-core compounds may be attributed to nanoscale smecticlike clusters that persist above the nematic-isotropic transition temperature, and shear align under shear flow; however, this mechanism has not yet been definitively confirmed.

引用

页数：4

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