Showing papers by "D. S. Shankar Rao published in 1998"
TL;DR: In this paper, the nematic phase of 4,4-(p-terphenyl)-bis and 2,3,4-tri(dodecyloxy)benzalimine is found to be biaxial, the biaaxial angle increasing with schlieren textures exhibited by the nematic phase have been between glass plates, as well as free standing consisting entirely of s or 2-brush disclinations.
Abstract: Conoscopic studies reveal that the nematic phase of 4,4-(p-terphenyl)-bis\[2,3,4-tri(dodecyloxy)benzal]imine is biaxial, the biaxial angle increasing with schlieren textures exhibited by the nematic phase have been between glass plates, as well as free-standing consisting entirely of s or 2-brush disclinations, confirming an earlier suggestion that the absence of 4-brush disclinations is evidence of biaxiality decreasing temperature The examined Films sandwiched films, exhibit a nematic schlieren texture
51 citations
Journal Article•
TL;DR: Conoscopic figures are presented demonstrating the occurrence of a biaXial nematic phase in the pure complex, the uniaxial-biaxial (Na-Nb) transition in binary mixtures, and the temperature variation of the bIAxiality near this transition.
37 citations
TL;DR: In this paper, an argument based on the ratio of the volume of the triphenylene core to the total volume was proposed to explain the hexagonally ordered columnar mesophase.
Abstract: High pressure investigations have been carried out on four successive homologues of the hexa-n-alkoxy triphenylene series exhibiting the hexagonally ordered columnar mesophase. The most remarkable feature is that the slope of the mesophase to isotropic phase boundary (dT/dP)1 bar shows a strong decrease with increasing chain length becoming zero for the 8th homologue. To explain this feature we propose an argument based on the ratio of the volume of the triphenylene core to the total volume.
8 citations