Effect of decoupled azimuthal and zenithal anchoring on smectic-C chevron structures

We present a study of the effect of decoupled azimuthal and zenithal weak anchoring on the transition between C1 and C2 chevron structures in smectic-C liquid crystals. We consider temperatures below the SmA-SmC transition and assume that the value of the smectic cone angle can be regarded as constant through the cell. By standard Euler-Lagrange minimization of the total energy we obtain a simple analytical expression for the equilibrium director twist angle in the C1 and C2 chevron states. Using this analytical form, we are able to compare the total energies of the C1 and C2 chevrons, and determine the globally stable chevron profile. We show that the C2 state is preferred when the azimuthal anchoring strength is relatively large, while C1 chevrons will dominate for strong zenithal anchoring.