Free-energy power expansion for orientationally ordered phases: energy and entropy.
نویسنده
چکیده
We propose an approach to the description of orientational phase transitions that utilizes the specific features of orientational energy and entropy. The approach is applied to building a model for nematic phases in materials with nonpolar parallelepiped-type molecules with symmetry D(2h). The model operates with complex order parameters, generalizes the Landau-de Gennes theory, and predicts the existence of a biaxial nematic phase for the fourth-order expansion of free energy.
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عنوان ژورنال:
- Physical review. E, Statistical, nonlinear, and soft matter physics
دوره 87 6 شماره
صفحات -
تاریخ انتشار 2013