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

形成有色液晶的分子通常是在外围具有亲水基团的芳族化合物。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。它们是盘状或碟状的形状，即使在稀溶液中，也有很强的倾向形成长堆叠，尽管也有分层相的报道。这些堆叠可以是位置无序的（N相），或者它们可以以六边形图案（M相）排列。虽然也有人提出过充水空心烟囱结构，但烟囱通常是简单的圆柱，分子结构和相行为之间的关系非常模糊。表面上微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的不必要的聚集可以使有希望的新配方变得无用。在这个提议中，我们试图获得这些化学品的结构-性质关系的定量理解。我们将合成一系列的萘胺磺酸衍生物，其中化学基团和几何形状以系统的方式变化。我们将实验研究相行为（也改变盐浓度和pH值），我们将进行计算机模拟研究国家的最先进的原子模拟模型。我们还将寻求发展简单的理论，以提供解释这些数据的基础框架。通过结合合成，相表征，模拟和理论，在这个系统的研究，我们的目标是揭示的基本规则，管理这一重要的和迷人的一类分子的聚集和相性质。

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.