Positional Order and Bond Orientational Order in the Liquid Crystal Smectic F Phase

Abstract

The smectic F phase occurring in TBBA homologues has been studied by means of X-ray scattering. It was already known that this phase consists of stacked uncorrelated layers. The temperature dependence of the in-plane positional correlation length, characteristic of a short range order has been analyzed. No divergency can be observed at the transition smectic F →2 smectic G. The existence of a long range bond-orientational order within a layer has been established. From the X-ray measurements, a basis is provided for the discussion of the behavior of the aliphatic chains.