Geometrical Model of the Tetragonal BPX Blue Phase
نویسنده
چکیده
Crystals of BPI and BP2 blue phases exhibit different crystalline structures un~ der sufficiently high electric field. When the dielectric anisotropy is positive, the same tetragonal phase, called BPX, has been observed when the field is applied, either along a two-fold axis of the BP1 phase, or along a four~fold axis of the BP2 phase. With the help of the geometrical models of cubic blue phases deduced from the analogy with the cubic lyotropic phases, we propose in
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