手性掺杂的DTC5Cn系列“扭曲弯曲”向列相（NTB）液晶材料的手性结构研究

“扭曲弯曲”向列相（NTB）是一种手性向列相，具有纳米级螺距的倾斜螺旋结构。直观地或动态地具体测量有关NTB相中的手性信息是目前面临的一个重要难题。手性掺杂NTB相液晶体系的设计是解决上述难题的有效手段。本项目拟在NTB相二聚体中引入高螺旋扭力掺杂剂，动态地研究掺杂剂的分子手性和液晶分子自发的纳米尺度手性之间的相互作用；进一步提出同步辐射圆二色谱成像法的概念全方位地识别和捕捉有关NTB相的超手性信息。通过系统地研究手性的引入、传输和呈现对二聚体材料液晶相的影响，揭示手性因素对液晶相的多形态呈现的作用，阐明手性相互作用如何在NTB相特殊的螺旋结构中显现这一前沿科学问题。为发展具有理想螺旋间距长度和自发极化的分子在光电子学的不同应用提供理论依据和技术方案。

“Twist-bend” nematic phase (NTB) is a chiral nematic phase with an inclined spiral structure possessing nanometer helical pitch. However, directly or dynamically measuring the chiral information in NTB phase is one of great challenges at present stage, and the design of doping the bent-core nematic liquid crystal (LC) with a chiral material is an effective strategy to solve this problem. In this project, chiral additives with high helical twisting power (HTP) will be introduced in dimer hosts to study the interactions between the molecular chirality and spontaneous ambidextrous chirality with nanoscale pitch. Furthermore, the concept of synchrotron radiation circular dichroism mapping (SR-CDM) method is proposed here to identify and capture the superchiral information of the NTB phase thoroughly. With this project, by systematically studying the influence of the introduction, transmission and presentation of chirality on the LC dimer materials, the relationship between chirality and the polymorphic LC behaviour of bent-core nematic liquid crystals will be illustrated. Furthermore, the frontier scientific issue that how chiral interactions manifest themselves in such heliconical structures will be elucidated. It will provide theoretical basis and technical protocol for a new molecular design with a desirable helical pitch length as well as spontaneous polarization that are useful for different applications in optoelectronics.