Ordering in two dimensions: Optical textures in monolayers

Abstract

Optical studies of Langmuir monolayers of simple amphiphiles such as fatty acids and esters by polarized fluorescence microscopy and Brewster-angle microscopy reveal a large variety of textures including stripes, stars, and spirals that closely resemble textures observed in liquid crystals. The textures represent large-scale ( > 10 ~) spontaneous organization of the molecular tilt azimuth. Phase transitions within the monolayer can be directly observed by marked changes in texture, revealing a complex phase diagram. Many of the textures can be explained by a Landau-deGennes theory of tilted hexatic phases that takes into account the broken-symmetry characteristic of amphiphiles at an interface. PACS 68.10 -Fluid surfaces and fluid-fluid interfaces. PACS 64.70.Md -Transitions in liquid crystals. PACS 61.30.Jf-Defects in liquid crystals. PACS 68.15 -Liquid thin films. PACS 01.30.Cc -Conference proceedings.

Chemical Microscopy

“…See also: References B3,B4,E26,E37,J11,K5,K67,K134,R7,R8,R9,AA23,CC10,FF8,FF15,FF20,LL3,LL7,LL14,LL24,LL32,LL34,LL38,PP15,QQ8.…”