Influence of the molecular tilt on the structure of smectic blue phases

Smectic blue phases (BP(sm)) are original physical systems of thermotropic liquid crystals, displaying a double geometrical frustration: the extension of chirality in the three spatial dimensions, such as classical blue phases, and the competition between smectic order and helical twist, such as twist grain boundary (TGB) phases. We report experimental evidence of the influence of the underlying TGB((A) or (C)) phase on the BP(sm) structure.