Chiral structures and defects of lyotropic chromonic liquid crystals induced by saddle-splay elasticity

Phys Rev E Stat Nonlin Soft Matter Phys. 2015 May;91(5):050501. doi: 10.1103/PhysRevE.91.050501. Epub 2015 May 22.

Abstract

An experimental and theoretical study of lyotropic chromonic liquid crystals (LCLCs) confined in cylinders with degenerate planar boundary conditions elucidates LCLC director configurations. When the Frank saddle-splay modulus is more than twice the twist modulus, the ground state adopts an inhomogeneous escaped-twisted configuration. Analysis of the configuration yields a large saddle-splay modulus, which violates Ericksen inequalities but not thermodynamic stability. Lastly, we observe point defects between opposite-handed domains, and we explain a preference for point defects over domain walls.