Spencer Russell K W, Ha Bae-Yeun, Saeidi Nima
Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1.
Department of Surgery, The Center for Engineering in Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114, USA.
Phys Rev E. 2022 May;105(5-1):054501. doi: 10.1103/PhysRevE.105.054501.
Chirality is a design feature of a number of biomolecules (e.g., collagen). In these molecules, cholesteric (chiral-nematic) behavior emerges from a combination of the tendency for the biopolymers to align (nematic interactions) and for the alignment direction to change with position, rotating around an axis normal to the alignment direction. This paper presents self-consistent field theory (SCFT) of chiral-nematic polymers, which takes into account polymer flexibility and the orientational degrees of freedom of polymer segments. Using the resulting SCFT, we construct a phase diagram showing regions of stability for isotropic, nematic, and cholesteric phases. Furthermore, we find that nematic interactions can stabilize the cholesteric phase, pushing the isotropic-cholesteric phase transition to lower cholesteric interaction strength, until the isotropic-nematic-cholesteric triple point is reached.
手性是许多生物分子（如胶原蛋白）的一种设计特征。在这些分子中，胆甾相（手性向列相）行为源于生物聚合物排列倾向（向列相互作用）以及排列方向随位置变化并围绕垂直于排列方向的轴旋转这两种倾向的结合。本文提出了手性向列型聚合物的自洽场理论（SCFT），该理论考虑了聚合物的柔韧性和聚合物链段的取向自由度。利用所得的自洽场理论，我们构建了一个相图，展示了各向同性相、向列相和胆甾相的稳定区域。此外，我们发现向列相互作用可以稳定胆甾相，将各向同性 - 胆甾相转变推向更低的胆甾相互作用强度，直至达到各向同性 - 向列 - 胆甾三相点。
