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A possible new phase of antagonistic nematogens in a disorienting field

T. G. Sokolovska·M. E. Cates·R. O. Sokolovskii
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Abstract

A simple model is proposed for nematogenic molecules that favor perpendicular orientations as well as parallel ones. (Charged rods, for example, show this antagonistic tendency.) When a small disorienting field is applied along $z$, a low density phase $N_-$ of nematic order parameter $S_z<0$ coexists with a dense biaxial nematic $N_b$. (At zero field, $N_-$ becomes isotropic and $N_b$ uniaxial.) But at stronger fields, a new phase $N_{+4}$, invariant under $π/2$ rotations around the field axis, appears in between $N_-$ and $N_b$. Prospects for finding the $N_{+4}$ phase experimentally are briefly discussed.

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T. G. Sokolovska, M. E. Cates, R. O. Sokolovskii. 2003-05-12. A possible new phase of antagonistic nematogens in a disorienting field. https://doi.org/10.1103/physrevlett.90.235701

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