ABSTRACT

The remarkable ability of certain molecules with a bent molecular shape to form hierarchically self-assembled helical building blocks with negative Gaussian or cylindrical curvature featuring in-layer hexatic ordering– so-called B4 phases – has quickly transformed these molecules into desirable building blocks for a variety of potential applications in optics, energy harvesting, and metamaterials. We here demonstrate that these building blocks, helical nanofilaments, helical microfilaments, and heliconical-layered nanocylinders, can to some degree be predictably blended. Supported by scanning as well as transmission electron microscopy and variable angle x-ray scattering data, the three bent-core compounds, each forming exactly one of these B4 morphologies, in binary mixtures at a 1:1 molar ratio, form either the third missing, or one of the two but with opposite handedness, or a random mixture of the two selected morphologies with larger overall dimensions. Furthermore, for two of the mixtures the a priori predicted handedness of the chiral filaments was experimentally confirmed. The third mixture with a priori predicted antagonistic handedness of the initial morphologies forms a combination of the two, one apparently achiral and the other one with opposite handedness.

摘要

具有弯曲分子形状的某些分子具有显着的能力，可以形成具有负高斯或圆柱曲率的分层自组装螺旋结构单元，具有层内六边形排序（即所谓的 B4 相），已迅速将这些分子转变为理想的结构单元，用于在光学、能量收集和超材料方面的各种潜在应用。我们在这里证明了这些构建块、螺旋纳米丝、螺旋微丝和螺旋层状纳米圆柱，可以在某种程度上可预测地混合。在扫描以及透射电子显微镜和可变角度 X 射线散射数据的支持下，三种弯曲核心化合物，每一种都恰好形成这些 B4 形态中的一种，以 1:1 的摩尔比以二元混合物形式存在，形成第三个缺失的, 或两者之一但具有相反的旋向性，或具有较大整体尺寸的两种选定形态的随机混合。此外，对于两种混合物，实验证实了手性长丝的先验预测的旋向性。具有先验预测的初始形态的拮抗旋向性的第三种混合物形成了两者的组合，一种明显是非手性的，另一种具有相反的旋向性。