Orientational ordering in the chiral smectic-C-F12* liquid crystal phase determined by resonant polarized x-ray diffraction - art. no. 050702

High-resolution resonant polarized x-ray diffraction experiments near the s ulfur K edge have been performed on free-standing liquid crystal films exhi biting the chiral smectic-C*(F12) phase. It is widely accepted that this ph ase has a four-layer repeat unit, but the internal structure of the repeat unit remains controversial. We report different resolved features of the re sonant x-ray diffraction peaks associated with the smectic-C*(F12) phase th at unambiguously demonstrate that the four-layer repeat unit is locally bia xial about the layer normal and that the measured angle, describing the bia xiality, is in good agreement with optical measurements.