Large Flow Birefringence of Nematogenic Bent-Core Liquid Crystals

Journal Article · Thu Jan 01 04:00:00 EST 2009 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.103.237803· OSTI ID:1019629

Bailey, C; Fodor-Csorba, K; Verduzco, R; Gleeson, J; Sprunt, S; Jakli, A

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.

• Research Organization: Brookhaven National Laboratory (BNL) National Synchrotron Light Source
• Sponsoring Organization: DOE - OFFICE OF SCIENCE
• DOE Contract Number: AC02-98CH10886
• OSTI ID: 1019629
• Report Number(s): BNL--95474-2011-JA
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 23 Vol. 103; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BIREFRINGENCE
LIQUID CRYSTALS
MOLECULAR WEIGHT
SHEAR
TRANSITION TEMPERATURE
VISCOSITY
national synchrotron light source