New Materials Based on the Self-Assembly of Polycyclic Aromatic Hydrocarbons

材料的性质不仅取决于组成分子的性质，还取决于这些分子的组织和相互作用的方式。因此，设计具有特定所需性能的新材料需要控制分子结构和这些分子的自组装。通过合成化学，我们可以制备新的分子，并通过进行特定的结构修饰来控制分子的性质。我们还可以通过加入指导分子自组装的单元来控制这些分子的组织。拟议的研究重点是通过制造基于多环芳烃的刚性分子构建块来设计和合成新材料，这些构建块将以可预测的方式自我组装，最终使我们能够控制材料的性能。 这项研究将集中在两个领域。研究的第一个目标是合成具有多个柔性链的新型多环芳烃。这些扁平的盘状分子有堆积成柱状并形成液晶相的趋势。这些液晶相是介于固体和液体之间的物质状态--它们是有序的流体。尽管有许多液晶材料的例子，但分子结构和形成液晶相的能力之间的关系还没有被很好地理解。通过制备具有系统结构变化的新型盘状液晶化合物，我们的目标是更好地了解控制液晶行为的因素。这样的材料可以表现出半导体或光导特性，使其在光伏太阳能电池、显示器用发光二极管(LED)和有机电子设备的薄膜晶体管等设备中具有潜在的应用价值。研究计划的第二个领域是使用芳香族化合物作为大环(大环)或扩展开放网络的构建块。这两种类型的材料预计都有很小的通道和孔，可能会被用来帮助根据大小分离化合物或捕获小分子。

The properties of materials depend not only on the nature of the constituent molecules, but also on the way that these molecules are organized and interact with each other. Therefore, the design of new materials with specific desired properties requires control of both molecular structure and the self-assembly of these molecules. Through synthetic chemistry, we can prepare new molecules and control molecular properties by making specific structural modifications. We can also control the organization of these molecules by incorporating units that direct molecular self-assembly. The proposed research focuses on the design and synthesis of new materials by making rigid molecular building blocks based on polycyclic aromatic hydrocarbons that will assemble themselves in predictable ways, ultimately allowing us to control the properties of the material. The research will focus on two areas. The first goal of the research is to make new polycyclic aromatic hydrocarbons with several flexible chains. These flat, disk-shaped molecules have a tendency to stack into columns and form liquid crystalline phases. These liquid crystalline phases are states of matter that are intermediate between a solid and a liquid – they are ordered fluids. Although there are numerous examples of liquid crystalline materials, the relationship between molecular structure and the ability to form a liquid crystalline phase is not well understood. By preparing new disk-shaped liquid crystalline compounds with systematic structural variations, we aim to better understand the factors that control liquid crystalline behavior. Materials such as these can exhibit semiconducting or photoconducting properties that make them potentially useful in devices such as photovoltaic solar cells, light emitting diodes (LEDs) for displays, and thin film transistors for organic electronics. The second area of the research program is to use aromatic compounds as building blocks for the preparation of macrocycles (large rings) or extended open networks. Both of these types of materials are expected to have small channels and pores and can potentially be used to aid in the separation of compounds based on size or to capture small molecules.