X-ray study of the layer structure in a high pre-tilt, anti-parallel aligned ferroelectric liquid crystal

X-ray diffraction has been used to investigate the layer structure of a fer roelectric liquid crystal device as a function of temperature. Obliquely ev aporated silicon monoxide alignment layers arranged anti-parallel to each o ther were used to align a 2 mu m sample of racemic SCE13. In the smectic A phase, the cell formed a uniform tilted layer with a tilt angle in good agr eement with the 25 degrees pre-tilt of the SiO. Below the transition to Sme ctic C there was evidence for a highly asymmetric chevron with layers orien ted away from the preferred alignment plane, together with domains of unifo rmly tilted layers. Further cooling to 30 degrees C caused the chevron stru cture to disappear, until only the uniformly tilted layer remained.