Changes in optical properties of TDO BAM BCC Langmuir films during a phase transition

Moscow University Physics Bulletin (Impact Factor: 0.25). 02/2011; 66(1):50-53. DOI: 10.3103/S002713491101022X


The isotherms of water molecule adsorption and the spectra of absorption, diffusion reflection, and polarization of reflected
light for hyperfine Langmuir films that were fabricated based on liquid crystals are investigated. Singularities in the reflection
spectra at the temperature of the structural phase transition (∼70°C) are revealed. Some reasonable assumptions on the nature
of the phase transition are made.

Download full-text


Available from: V. B. Zaytsev, Oct 03, 2015
19 Reads
  • [Show abstract] [Hide abstract]
    ABSTRACT: Electric and electro-optical properties of a smectic liquid crystal (LC) compound formed by rod-like molecules have been investigated in the thin film sandwich geometry typically used in solid-state technology. Thin (~10–30 nm) Langmuir–Blodgett (LB) films of the compound (tetradecyl homologue (n=14) of the series p-oxybenzylidene-p′-amino-2-methylbutyl(α-cyano)cinnamate) were transferred onto glasses covered with a transparent electrode and supplied with a top electrode evaporated in vacuum. In contrast to the LC bulk, thin films of the compound manifest only a solid crystalline phase throughout the whole temperature range (20–110 °C) investigated. Ferroelectric properties of the films (covering linear electro-optic effect, pyroeffect and polarization switching) have been observed in the whole temperature range studied.
    Thin Solid Films 10/2008; 516(24):8905-8908. DOI:10.1016/j.tsf.2007.11.065 · 1.76 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Molecules which form Langmuir-Blodgett (LB) films are, in many respects, similar to molecules which can form smectic liquid crystals. It is thus surprising that there is such a small overlap in the literature between these two fields of study. In this paper a review of publications dealing with this overlapping region is given. Films analogous to those formed by the LB method can also be formed by thermal evaporation in vacuo and by the transfer of freely suspended films of liquid crystals initially formed across apertures in thin glass or metal plates. Some instances of these two techniques are also discussed
    Molecular Crystals and Liquid Crystals 01/2001; 355(1-1):289-303. DOI:10.1080/10587250108023666 · 0.58 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The transfer of freely suspended (FS) liquid-crystalline (LC) films onto solid suports offers the possibility of creating smectic multilayer films that, depending on the material and the phase state, can in principle be monolayer (head-to-tail) or bilayer (head-to-head and tail-to-tail) structures. The use of amphiphilic liquid-crystalline compounds enables the direct comparison of transferred freely suspended (TFS) films with Langmuir-Blodgett (LB) films of the same material. In the case of ethyl-4′-n-octyloxybiphenyl-4-carboxylate (1) the LB films are originally deposited as bilayers that rearrange to monolayer structure within hours. The TFS films of 1 exhibit a monolayer structure with the same layer spacing as the rearranged LB film (24 Å). However, the thermal stability of the TFS films is superior to that of LB films, which start to melt at 80 °C. The TFS films melt at 110°C, which is also the clearing point of the bulk material. An additional advantage of the TFS films is that they can be obtained as monodomains.
    Thin Solid Films 04/1992; 210-211:504-507. DOI:10.1016/0040-6090(92)90325-6 · 1.76 Impact Factor