Hydrodynamics of three-dimensional stacked hexatic liquid crystals

Abstract
The hydrodynamic equations for three-dimensional stacked hexatic liquid crystals, i.e., for hexatic-B and its tilted analogs, smectic-F and smectic-I, are presented. Differences and similarities to the hydrodynamics of smectic-A and smectic-C are discussed and the role of the additional variable characterizing the bond orientational order is elucidated.