Large assembly formation via a two-step process in a chromonic liquid crystal.

Journal Article (Journal Article)

IR-806 is a near-infrared cyanine dye that forms assemblies in aqueous solutions which in turn orientationally order into a liquid crystal phase at concentrations as low as 0.5 wt %. Unlike many chromonic liquid crystals, the absorption spectrum of IR-806 changes dramatically with concentration, showing an isodesmic assembly process at lower concentrations followed by a second process at higher concentrations that is not isodesmic. The lower concentration assembly process is characterized by a free energy change per molecule of about 9 k(B)T, not unlike other chromonic systems. However, X-ray scattering measurements suggest that the assemblies that form during the higher concentration process are much larger than what is observed for many chromonic liquid crystals. Although there is a transitional region between the liquid crystal and isotropic phases of 10-15 °C, unlike most chromonic liquid crystals, no biphasic region is observed using polarizing microscopy.

Full Text

Duke Authors

Cited Authors

  • Mills, EA; Regan, MH; Stanic, V; Collings, PJ

Published Date

  • November 2012

Published In

Volume / Issue

  • 116 / 45

Start / End Page

  • 13506 - 13515

PubMed ID

  • 23092355

Electronic International Standard Serial Number (EISSN)

  • 1520-5207

International Standard Serial Number (ISSN)

  • 1520-6106

Digital Object Identifier (DOI)

  • 10.1021/jp306135w


  • eng