Magnetic susceptibility studies on ferrofluid doped lyotropic liquid crystal systems

Abstract

We have carried out mass magnetic susceptibility studies on water based ferrofluid doped (1µl/ ml) binary lyotropic liquid crystal (LLC) systems consisting of a) rod-like and b) disc-like micelles and also on a ternary lyotropic liquid crystal system consisting of rodlike micelles; as a function temperature using a Faraday balance. In the case of ferrofluid doped discotic LLC, the magnetic susceptibility) is positive and found to increase more than one order of magnitude with respect to that of undoped one indicating a strong coupling between the magnetic nanoparticles and the micelles. However for LLC system consisting of rod-like micelles, only a marginal increase in susceptibility is seen on doping which can be attributed to the changes in the micellar sizes..In the case of ternary LLC system, temperature dependent magnetic susceptibility hysteresis is seen for both the doped and undoped samples. The observed hysteresis increases with increasing concentration of ferrofluid duping in the system