INTERFACES AND GRAIN-BOUNDARIES OF LAMELLAR PHASES

Interfaces between lamellar and disordered phases, and grain boundarie s within lamellar phases: are investigated employing a simple Landau f ree energy functional. The former are examined using analytic, approxi mate methods in the weak segregation limit, leading to density profile s which can extend over many wavelengths of the lamellar phase. The la tter are studied numerically and exactly. We find a change from smooth chevron configurations typical of small tilt angles to distorted omeg a configurations at large tilt angles in agreement with experiment. (C ) 1998 Elsevier Science B.V. All rights reserved.