Paper Title:
Phase Transition, Birefringence and Orientational Order Parameter Studies in Four Members of Benzylidene Aniline Liquid Crystals
  Abstract

The nature of the phase transitions across isotropic–nematic (IN) and nematic–smectic-A (N-SmA) are carried out using density measurements in N-(p-n-ethoxy benzylidene)-p-n-pentyl aniline, 2O.5, N-(p-n-methoxy benzylidene)-p-n-pentyloxy aniline, 1O.O5, N-(p-n-ethyl benzylidene)-p-n-dodecyl aniline, 2.12 and N-(p-n-butyl benzylidene)-p-n-dodecyl aniline, 4.12. The compounds exhibit IN, IN, IN and INSmA phase sequences respectively with varying thermal ranges suitable for the study of birefringence. The birefringence studies are carried out using Newton’s rings and wedge techniques which provide δn = (ne - no) (the birefringence) ne, and no respectively. The orientational order parameter, S is evaluated (i) directly from δn and Δn (the birefringence in perfect order), independent of the local field that the nematic molecule experiences and (ii) from molecular polarizabilities estimated from ne, no and density values assuming isotropic as well as anisotropic field that the nematic molecule experiences. The estimated order parameter from the different techniques is compared with one another and with the literature data.

  Info
Periodical
Solid State Phenomena (Volumes 181-182)
Chapter
I. Physics of Liquid Crystals
Edited by
Yuan Ming Huang
Pages
115-119
DOI
10.4028/www.scientific.net/SSP.181-182.115
Citation
P.V. D. Prasad, G. P. Rani, V.G.K.M. Pisipati, "Phase Transition, Birefringence and Orientational Order Parameter Studies in Four Members of Benzylidene Aniline Liquid Crystals", Solid State Phenomena, Vols. 181-182, pp. 115-119, 2012
Online since
November 2011
Export
Price
$32.00
Share

In order to see related information, you need to Login.

In order to see related information, you need to Login.

Authors: H. Ohkita, A. Tagaya, Y. Koike
Abstract:Birefringence induced by the orientation of polymer main chains during injectionmoulding or extrusion processing restricts the application of...
143
Authors: B.R. Rajeswari, P. Pardhasaradhi, M. Ramakrishna Nanachara Rao, P.V. Datta Prasad, D. Madhavi Latha, V.G.K.M. Pisipati
I. Physics of Liquid Crystals
Abstract:The refractive indices measurements are carried out using a modified spectrometer connected with wedge shaped cell and also the direct...
75
Authors: M. Ramakrishna Nanachara Rao, P.V. Datta Prasad, V.G.K.M. Pisipati, D. Madhavi Latha
I. Physics of Liquid Crystals
Abstract:Refractive indices measurements are carried out in four alkoxy benzylidene anilines viz., N-(p-n-methoxy and ethoxy...
102
Authors: Dai Li, Lin Ling Bai, Zi Qiang Huang
IV. Applications of Liquid Crystals
Abstract:Based on liquid crystal electrically controlled birefringence, the paper theoretically deduces liquid crystal variable retarders’ (LCVRs)...
261
Authors: Azman Kasim, H. Azhan, Syamsyir Akmal Syamsyir, Mardhiah Abdullah, M.R.S. Nasuha
Chapter 2: Ceramics and Glasses
Abstract:Many trivalent rare earth ions such as Er3+, Tm3+, Ho3+, Pr3+ and Nd3+ were doped as...
193