Marangoni convection in cyanobiphenyl liquid crystals under temperature gradient

Abstract

We investigated the Marangoni convection induced in the cyanobiphenyl liquid crystalline materials of 5, 6, 7 and 8CB in sandwich cells under a temperature gradient especially near transition points. We analysed the flow field near air interface by using fluorescence photo-bleaching method. In all the samples described above, we observed the appearance of the Marangoni convection, where the flow direction depended on the sample and temperature range. On the basis of these experimental results, we discuss the relation between surface tension gradient and flow field in cyanobiphenyl liquid crystals.