文献类型：期刊文献

英文题名：Twist-bend nematic phase and heliconical superstructures of thioether-linked liquid crystal dimers

作者：Liu, Huixian[1];Guo, Li[1];Zhan, Yuxing[1];Ren, Yiran[1];Wang, Xiangqian[1];Hu, Honglong[1];Yuan, Conglong[1,2];Zheng, Zhi-Gang[1]

机构：[1]East China Univ Sci & Technol, Sch Phys, Shanghai 200237, Peoples R China;[2]Soochow Univ, Engn Res Ctr Digital Imaging & Display, Minist Educ, Suzhou 215006, Peoples R China

年份：2025

卷号：163

期号：13

外文期刊名：JOURNAL OF CHEMICAL PHYSICS

收录：;EI(收录号：20254019274001);WOS:【SCI-EXPANDED(收录号:WOS:001586172400018)】；

基金：The authors acknowledge the support from the National Key Research and Development Program of China (Grant No. 2022YFA1203700), National Natural Science Foundation of China (Grant Nos. T2488302, 62275081, 62035008, 22305079, and 62505085), Innovation Program of Shanghai Municipal Education Commission, Scientific Committee of Shanghai (Grant No. 2021-01-07-00-02-E00107), Chenguang Program of Shanghai Education Development Foundation and Shanghai Municipal Education Commission (Grant No. 24CGA29), Shanghai Sailing Program (Grant Nos. 23YF1409000 and 24YF2709100), Postdoctoral Fellowship Program of CPSF (Grant No. GZB20240218), and Engineering Research Center of Digital Imaging and Display, Ministry of Education, Soochow University (Grant No. SDGC2436).

语种：英文

外文关键词：Blending - Nematic liquid crystals - Sulfur - Supercooling

摘要：The twist-bend nematic (N-TB) phase, characterized by a spontaneously formed nanoscale heliconical superstructure from achiral liquid crystal (LC) dimers, represents a fundamental advance in soft matter physics and photonic material design. Sulfur-containing LC dimers, with enhanced molecular flexibility and reduced bond angles, offer promising opportunities for functional N-TB materials but remain limited by thermal instability and poorly characterized physical parameters. Herein, we comprehensively investigate a series of thioether-linked symmetric LC dimers (CBSnSCB, n = 3, 5, 7) and their mixtures, revealing how molecular architecture governs phase transition behavior. Judicious blending of multiple homologs significantly suppresses crystallization and extends the supercooled N-TB phase stability to room temperature while preserving the phase sequence. Dielectric and elastic analyses demonstrate positive dielectric anisotropy and exceptionally low bend elastic constants, attributed to sulfur-mediated molecular flexibility, which can be further modified by incorporating conventional LCs. Leveraging these unique properties, electrically tunable oblique helicoidal cholesteric superstructures with continuously modulated photonic bandgaps across the entire visible spectrum are constructed. This study establishes a structure-property-function relationship in sulfur-containing LC dimers and offers a versatile platform for engineering stable, functional soft matter systems and adaptive photonic applications.