Macroscopic dynamics of polar nematic liquid crystals

• Verfasst von: Brand, Helmut R. [VerfasserIn]
• Verfasst von: Pleiner, Harald [VerfasserIn]
• Verfasst von: Ziebert, Falko [VerfasserIn]
• Titel: Macroscopic dynamics of polar nematic liquid crystals
• Verf.angabe: Helmut R. Brand, Harald Pleiner, Falko Ziebert
• E-Jahr: 2006
• Jahr: 30 August 2006
• Umfang: 7 S.
• Fussnoten: Gesehen am 21.09.2022
• Titel Quelle: Enthalten in: Physical review / E
• Ort Quelle: College Park, Md. : APS, 1993
• Jahr Quelle: 2006
• Band/Heft Quelle: 74(2006), 2, Artikel-ID 021713, Seite 1-7
• ISSN Quelle: 1550-2376
• DOI: doi:10.1103/PhysRevE.74.021713
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 180786443X

Abstract

We present the macroscopic equations for polar nematic liquid crystals. We consider the case where one has both, the usual nematic director, ˆn, characterizing quadrupolar order as well as the macroscopic polarization, P, representing polar order, but where their directions coincide and are rigidly coupled. In this case one has to choose P as the independent macroscopic variable. Such equations are expected to be relevant in connection with nematic phases with unusual properties found recently in compounds composed of banana-shaped molecules. Among the effects predicted, which are absent in conventional nematic liquid crystals showing only quadrupolar order, are pyro-electricity and its analogs for density and for concentration in mixtures as well as a flow alignment behavior, which is more complex than in usual low molecular weight nematics. We also discuss the formation of defect structures expected in such systems.