Rayleigh scattering from column undulations in a discotic liquid crystal.

Depolarized Rayleigh scattering on a columnar discotic liquid crystal is described. Column undulations and mode quantization allow the scattering to be visible only for two directions of reciprocal space, and for well-defined light propagation angles. The observed constant angular extension of the scattering shows that column undulations are not controlled by curvature elasticity, but by an anisotropic 3D solidlike elasticity. This behavior is probably associated with column entanglement, as recently discussed by Prost