MOLECULAR-DYNAMICS STUDIES OF SMECTIC-B LIQUID-CRYSTALS OF SOFT PARALLEL SPHEROCYLINDERS WITH SIXFOLD BOND ORIENTATIONAL ORDER

We analyze the smectic liquid crystal phase realized by soft-core repulsive forces alone. Molecular dynamics simulations under hydrostatic pressure are performed for a system of soft, parallel spherocylinders. This system undergoes a clear first-order transition by heating from crystalline solid to the smectic B phase which has sixfold bond orientational order. In this smectic phase, the three-dimensional sixfold bond orientational order is induced by interacting layers of two-dimensional hexatic order. This is the first demonstration that models with soft-core repulsive intermolecular forces alone predict a hexatic B liquid crystal phase.