TRUE INCOMMENSURATE PHASE IN MIXTURES OF TWO POLAR LIQUID CRYSTALLINE MATERIALS

High-resolution x-ray scattering measurements of 23.0 and 28.4 mole % mixtures of TBBA in DB6 have led to the observation of a true incommensurate phase in a liquid crystal system. The phase is characterized by two primary quasi-Bragg reflections at incommensurate wave vectors. X-ray scattering measurements of a freely suspended film in the new phase have revealed that it possesses sixfold in-plane symmetry, suggesting it to be an incommensurate crystal- $B$ or - $E$ phase.