Self-assembly of chromonic liquid crystals: a combined experimental and theoretical approach.

形成慢性液晶的分子通常是具有亲水基团的芳烃分子。这些基团使化合物可溶于水。许多染料和药物分子都属于这种类型。它们呈圆盘状或板状，即使在稀溶液中也有形成长堆的强烈倾向，尽管也有分层相的报道。这些堆叠可以是位置无序的（N相），也可以排列成六角形（M相）。通常烟囱是简单的柱子，尽管也有人提出了充水的空心烟囱结构。分子结构和相行为之间的关系是非常模糊的。表面上很小的结构差异会对相图产生很大的影响。这具有实际意义，因为染料和药物分子不必要的聚集可能使有希望的新配方无效。在这个建议中，我们试图获得这些化学品的结构-性质关系的定量理解。我们将合成一系列萘胺磺酸衍生物，其中的化学基团和几何结构以系统的方式变化。我们将通过实验检查相行为（也改变盐浓度和pH值），我们将在最先进的原子模拟模型上进行计算机模拟研究。我们还将寻求发展简单的理论，为解释这些数据提供一个基础框架。通过在本系统研究中结合合成、相表征、模拟和理论，我们的目标是揭示控制这类重要而迷人的分子的聚集和相性质的基本规则。

The molecules that form chromonic liquid crystals are typically aromatics with hydrophilic groups on the periphery. These groups make the compounds soluble in water. Many dye and drug molecules are of this type. They are disc-like or plank-like in shape and have a strong tendency, even in dilute solution, to form long stacks, though layered phases have also been reported. These stacks may be positionally disordered (N phase) or they may be arranged in hexagonal patterns (M phase). Often the stacks are simple columns, though water-filled hollow chimney structures have also been proposed.The relationship between the molecular structure and the phase behaviour is very obscure. Seemingly small structural differences can have large effects on the phase diagram. This has practical implications, for unwanted aggregation of dye and drug molecules can render promising new formulations useless.In this proposal we seek to obtain a quantitative understanding of the structure-property relations of these chemicals. We will synthesise a series of naphthylamine sulphonic acid derivatives in which the chemical groups and the geometry are varied in a systematic way. We will experimentally examine the phase behaviour (varying also the salt concentration and the pH) and we will carry out computer simulation studies on state-of-the-art atomistic simulation models. We will also seek to develop simple theories to provide an underpinning framework to interpret these data. By combining synthesis, phase characterisation, simulation and theory in this systematic study, we aim to uncover the basic rules that govern the aggregation and phase properties of this important and fascinating class of molecules.