TITLE:
Polarizabilities and Orientational Order Parameter in N-(p-n-Ethoxybenzylidene)- p-n-Alkoxy Anilines, 2O.Om LC Compounds
AUTHORS:
Putcha Srinivasa Sastry, Chintalapati Srinivas, Pokkunuri Pardhasaradhi, Venkata Gopala Krishna Murthy Pisipati
KEYWORDS:
Orientstonal Order Parameter, S, 2O.Om LC Compounds, Vuks Isotropic Model, Neugebauer Anisotropic Model, Nematic Phase
JOURNAL NAME:
Journal of Surface Engineered Materials and Advanced Technology,
Vol.6 No.3,
July
28,
2016
ABSTRACT: n.m, n.Om, nO.m and nO.Om compounds play an important role in the fundamental and applied aspects. As a part of our systematic studies of the above homologous series regarding the synthesis, characterization and phase transition studies, here the authors report the polarizabilities and orientational order parameter, S in N-(p-n-ethoxybenzylidene)-p-n-alkoxy anilines, 2O.Om with m = 3 to 10 liquid crystalline compounds except with m = 5 which has been already published. The rest of the compounds exhibit the nematic LC phase except with m = 10 which shows the smectic-C phase along the nematic phase which is originally not detected by Godzwon et al. But the author’s observations with TM and differential scanning calorimeter have shown the existence on SmC phase in addition to nematic phase. Further, SmC is clarified using the histogram technique whose details are given below and are published elsewhere. The orientstonal order parameter, S is estimated using different methods and compared with the value obtained from birefringence, δn = (ne – no) where no field model is used. It is observed in these compounds case as in other LC compounds Vuks isotropic model is favored compared to that of anisotropic model proposed by Neugebauer.