WEDGE-SCREW DISPIRATION IN SMECTIC LIQUID-CRYSTALS WITH ANTIFERROELECTRIC ORDER

Using the approximative expression for the elastic energy density of t he antiferroelectric (AF) liquid crystal the elastic self-energy of (p i, b)-wedge-screw dispiration is estimated. Then the elastic interacti on between (pi, b)-wedge-screw dispiration and (2pi)-wedge disclinatio n in AF liquid crystals is investigated. The attraction of dislocation part of dispiration with (2pi)-wedge disclination can lead to the for mation of (3pi)-wedge-screw dispiration. When (2pi)-wedge disclination is trapped by (2d)-screw dislocation the resulting (2pi, 2d)-dispirat ion can dissociate into a pair of two (pi, d)-dispirations.