Articles written in Pramana – Journal of Physics
Volume 1 Issue 1 July 1973 pp 12-20 Liquids
A theory is developed of the anomalous magnetic and electric birefringence in the isotropic phase of nematic liquid crystals taking into account orientational correlations between neighbouring molecules. Use is made of a modification of Bethe’s method due to Krieger and James, and the properties of the system are derived in terms of a single parameter, viz., the two-particle interaction constant. The expressions for the magnetic and electric birefringence are similar in form to those given by the phenomenological model of de Gennes. Theoretical curves for
Volume 5 Issue 2 August 1975 pp 101-106 Liquids
It is shown that the essential features of Helfrich’s permeation model for flow along the helical axis of a cholesteric liquid crystal can be derived approximately on the basis of the Ericksen-Leslie theory.
Volume 8 Issue 1 January 1977 pp 22-35 Liquids
The different approximations that have been used in applying Bethe’s cluster model to the nematic-isotropic phase transition are examined. It is shown that the introduction of a higher order term in the mean field potential of an outer molecule of the cluster improves the consistency of the theory considerably. In particular, the importance of satisfying Chang’s relation is emphasized. Calculations are presented of the long and short range order parameters, heat of transition and specific heat for different values of
Volume 9 Issue 5 November 1977 pp 471-480 Liquids
Thermotropic mesomorphism has been observed in pure compounds consisting of simple disc-like molecules, viz., benzene-hexa-
Volume 27 Issue 5 November 1986 pp 1- Letter
The paper reports new nematic liquid crystals that are paramagnetic.
Volume 53 Issue 1 July 1999 pp 3-11 Liquid Crystals And Other Soft Materials
We have studied the electrical conductivity of well aligned samples of hexahexylthiotriphenylene (HHTT) in the pure as well as doped states. The dopant used was a small concentration (0.62 mole %) of the electron acceptor trinitrofluorenone (TNF). In the columnar phases, doping causes the AC(1 kHz) conductivity along the columnar axis (
We also report the first thermoelectric power studies on these ‘molecular wires’. The sign of the thermoelectric power is in conformity with the expected nature of the charge carriers, namely, holes.
Volume 97, 2023
Continuous Article Publishing mode
Click here for Editorial Note on CAP Mode