ABSTRACT
On the basis of Landau–de Gennes theory and the finite-difference iterative method, spontaneous chiral structures in cylinders with degenerate planar boundary conditions are investigated. A double-twist director configuration can be achieved by the saddle–splay contribution, corresponding to the L24 term in Landau–de Gennes theory. The twist angle increases as the radius R of the cylinder is reduced because the curvature of the cylindrical surface becomes larger. Moreover, we find fine structures of the domain walls and point defects between opposite-handed domains. An energy comparison shows that domain walls are the stable state for K24/K> 0.6 (K11 = K33 = K, K11, K33 and K24 are the splay, bend, saddle–splay elastic constants in Frank theory), whereas point defects are the stable state for K24/K< 0.6.
Graphical abstract
Schematic of the chiral director configuration for domain walls (a, c) and point defects (b, d), induced by saddle-splay elasticity.
![Schematic of the chiral director configuration for domain walls (a, c) and point defects (b, d), induced by saddle-splay elasticity.](/cms/asset/117ef19e-8ef0-4430-9868-bca8b4ec2e7a/tlct_a_1692255_uf0001_oc.jpg)
Disclosure statement
No potential conflict of interest was reported by the authors.