Novel liquid crystalline structure in langmuir monolayers of amphiphilic azobenzene derivative

Yuka Tabe, Hiroshi Yokoyama

Research output: Contribution to journalArticle

28 Citations (Scopus)

Abstract

Depolarized Brewster-angle microscopy revealed a novel two-dimensional (2D) mesophase in Langmuir monolayers of 4-octyl-4′-(3-carboxytrimethyleneoxy) azobenzene, characterized by ubiquitous schlieren textures resulting from the long-range order of in-plane molecular orientations. The lack of half-integral strength disclinations and the presence of a regular array of π-walls, across which the in-plane orientation changes by 180 degrees, indicate the vectorial nature of the underlying order parameter. The monolayer can, therefore, be viewed as a single layer of a bulk smectic C phase or as a 2D polar nematic phase, except for the obvious absence of mirror symmetry with respect to the layer plane. In contrast to the experience with bulk liquid crystalline phases, higher-order point disclinations were often found stable in the monolayer.

Original languageEnglish
Pages (from-to)2472-2476
Number of pages5
JournalJournal of the Physical Society of Japan
Volume63
Issue number7
Publication statusPublished - 1994 Jul
Externally publishedYes

Fingerprint

monomolecular films
Brewster angle
liquids
textures
mirrors
microscopy
symmetry

Keywords

  • π-wall
  • 2D liquid crystal
  • Brewster-angle microscopy
  • Langmuir monolayer
  • Modulated phase
  • Point disclination
  • Schlieren texture

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Novel liquid crystalline structure in langmuir monolayers of amphiphilic azobenzene derivative. / Tabe, Yuka; Yokoyama, Hiroshi.

In: Journal of the Physical Society of Japan, Vol. 63, No. 7, 07.1994, p. 2472-2476.

Research output: Contribution to journalArticle

@article{f63f39d25baa4bc7bd933c3bb5b21070,
title = "Novel liquid crystalline structure in langmuir monolayers of amphiphilic azobenzene derivative",
abstract = "Depolarized Brewster-angle microscopy revealed a novel two-dimensional (2D) mesophase in Langmuir monolayers of 4-octyl-4′-(3-carboxytrimethyleneoxy) azobenzene, characterized by ubiquitous schlieren textures resulting from the long-range order of in-plane molecular orientations. The lack of half-integral strength disclinations and the presence of a regular array of π-walls, across which the in-plane orientation changes by 180 degrees, indicate the vectorial nature of the underlying order parameter. The monolayer can, therefore, be viewed as a single layer of a bulk smectic C phase or as a 2D polar nematic phase, except for the obvious absence of mirror symmetry with respect to the layer plane. In contrast to the experience with bulk liquid crystalline phases, higher-order point disclinations were often found stable in the monolayer.",
keywords = "π-wall, 2D liquid crystal, Brewster-angle microscopy, Langmuir monolayer, Modulated phase, Point disclination, Schlieren texture",
author = "Yuka Tabe and Hiroshi Yokoyama",
year = "1994",
month = "7",
language = "English",
volume = "63",
pages = "2472--2476",
journal = "Journal of the Physical Society of Japan",
issn = "0031-9015",
publisher = "Physical Society of Japan",
number = "7",

}

TY - JOUR

T1 - Novel liquid crystalline structure in langmuir monolayers of amphiphilic azobenzene derivative

AU - Tabe, Yuka

AU - Yokoyama, Hiroshi

PY - 1994/7

Y1 - 1994/7

N2 - Depolarized Brewster-angle microscopy revealed a novel two-dimensional (2D) mesophase in Langmuir monolayers of 4-octyl-4′-(3-carboxytrimethyleneoxy) azobenzene, characterized by ubiquitous schlieren textures resulting from the long-range order of in-plane molecular orientations. The lack of half-integral strength disclinations and the presence of a regular array of π-walls, across which the in-plane orientation changes by 180 degrees, indicate the vectorial nature of the underlying order parameter. The monolayer can, therefore, be viewed as a single layer of a bulk smectic C phase or as a 2D polar nematic phase, except for the obvious absence of mirror symmetry with respect to the layer plane. In contrast to the experience with bulk liquid crystalline phases, higher-order point disclinations were often found stable in the monolayer.

AB - Depolarized Brewster-angle microscopy revealed a novel two-dimensional (2D) mesophase in Langmuir monolayers of 4-octyl-4′-(3-carboxytrimethyleneoxy) azobenzene, characterized by ubiquitous schlieren textures resulting from the long-range order of in-plane molecular orientations. The lack of half-integral strength disclinations and the presence of a regular array of π-walls, across which the in-plane orientation changes by 180 degrees, indicate the vectorial nature of the underlying order parameter. The monolayer can, therefore, be viewed as a single layer of a bulk smectic C phase or as a 2D polar nematic phase, except for the obvious absence of mirror symmetry with respect to the layer plane. In contrast to the experience with bulk liquid crystalline phases, higher-order point disclinations were often found stable in the monolayer.

KW - π-wall

KW - 2D liquid crystal

KW - Brewster-angle microscopy

KW - Langmuir monolayer

KW - Modulated phase

KW - Point disclination

KW - Schlieren texture

UR - http://www.scopus.com/inward/record.url?scp=0012185486&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0012185486&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0012185486

VL - 63

SP - 2472

EP - 2476

JO - Journal of the Physical Society of Japan

JF - Journal of the Physical Society of Japan

SN - 0031-9015

IS - 7

ER -