Chirality Detection Using Nematic Liquid Crystal Droplets on Anisotropic Surfaces
Artikel i vetenskaplig tidskrift, 2016

Nematic liquid crystals (NLCs) form helical macroscopic structures through chiral induction when doped with chiral species. We describe a very simple, though highly sensitive method for determination of handedness and pitch of the induced twist in the case of very weak twisting powers of such chiral dopants. A tiny drop typically less than 10 nL-of the chiral doped NLC is placed on a plate promoting a uniform planar surface anchoring of the liquid crystal director. At the curved NLC air interface the anchoring is homeotropic and in the sessile droplets we get a locally twisted hybrid director structure with a disclination line extending across the droplet. The configuration of the disclination line (S-like or backwards S-like) reveals the sign of twisting power and extremely large pitch values in the range of 10 mm can easily be measured. We demonstrate the method using the standard NLC 4-cyano-4'-pentylbiphenyl (5CB), weakly doped with the chiral material 2-hydroxy-2-phenylacetic acid (mandelic acid).

naturwissenschaften

helical twisting power

cell

configuration

egemey.h

p599

cholesteric pitch

polarization

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Materials Science

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v58

phases

p3

model

1974

raley jp

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1971

physical review a

p1881

v10

molecular chirality

v91

index

egemeyer h

Författare

Per Rudquist

Chalmers, Mikroteknologi och nanovetenskap (MC2), Fotonik

C. F. Dietrich

Universität Stuttgart

A. G. Mark

Max Planck-institutet

F. Giesselmann

Universität Stuttgart

Langmuir

0743-7463 (ISSN) 1520-5827 (eISSN)

Vol. 32 24 6140-6147

Ämneskategorier

Materialkemi

DOI

10.1021/acs.langmuir.6b00382

PubMed

27244587

Mer information

Senast uppdaterat

2018-03-19