Phase transition between the cholesteric and twist grain boundary C phases

نویسنده

  • I. Luk’yanchuk
چکیده

The upper critical temperature Tc2 for the phase transition between the Cholesteric phase (N∗) and the Twist Grain Boundary C phase with the layer inclination tilted to the pitch axis (TGBCt) in thermotropic liquid crystals is determined by the mean field Chen-Lubensky approach. We show that the N-TGBCt phase transition is split in two with the appearance of either the TGBA or the TGB2q phase in a narrow temperature interval below Tc2. The latter phase is novel in being superposed from two degenerate TGBCt phases with different (left and right) layers inclinations to the pitch axis. Typeset using REVTEX

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تاریخ انتشار 2008