Theory and simulation of soft condensed matter

软凝聚态物质包括各种各样的材料，包括液体、玻璃、凝胶、胶体和颗粒材料，它们在自然界中无处不在，在工程材料和设备中也无处不在。例如，液体是物质的主要形式之一，但其无序的结构和复杂的分子运动使其难以理解。当液体迅速冷却时，它会被困在非晶态玻璃中，这种玻璃具有液体的结构，但具有固体的机械刚性。当缓慢冷却时，同样的液体可以冻结成晶体，具有长范围的周期性顺序。在某些情况下，这些晶体具有大而复杂的单细胞，需要在许多长度尺度上进行结构组织。导致玻璃化和成核的分子过程仍然是未知的。胶体，甚至是宏观的、无热的、颗粒状的材料，如沙子，都表现出与液体相似的复杂粒子运动和相行为，这表明有重要的潜在原理将这些看似不同的物质形式联系在一起。本提案描述了一个研究软凝聚态系统的结构、热力学和动力学性质的研究项目，旨在利用分子理论和计算机模拟来解决这些基本问题。特别是，我们专注于理解粒子聚集在一起的能力如何影响液体的热力学和动力学。我们的目标是研究当系统受到限制时，这些变化是如何发生的。这将使我们深入了解玻璃是如何形成的，以及哪些因素影响了它们的性质。它还将帮助我们了解流体在碳纳米管和沸石等受限系统中的运动方式。我们也对成核现象感兴趣，并计划开发严格的理论方法来计算一系列系统的成核速率，包括复杂晶体的成核和大气气溶胶中的成核。虽然该提案的主要工作重点是基础性质，但我们正在利用通过研究获得的知识探索技术和自然的重要应用。例如，我们正在利用粒子在受限环境中移动的方式和单文件扩散的知识来开发用于分离混合物的纳米流体装置。此外，我们对成核的研究将用于开发和测试准确的理论，以预测大气气溶胶中的颗粒生长和成核，因此它们可以用于云和大气建模。

Soft condensed matter encompasses a diverse range of materials, including liquids, glasses, gels, colloids, and granular materials, that appear ubiquitously throughout nature, and in engineered materials and devices. For example, liquids represent one of the main forms of matter, but their disordered structure and complex molecular motions have made them difficult to understand. When a liquid is cooled rapidly, it can become trapped in an amorphous glass which has the structure of a liquid but the mechanical rigidity of a solid. When cooled slowly, that same liquid can freeze to a crystal, with long range periodic order. In some cases, these crystals have large, complex unit cells that require structural organization over many length scales. The molecular processes leading to vitrification and nucleation are still unknown. Colloids and even macroscopic, athermal, granular materials, such as sand, exhibit the similar types of complex particle motion and phase behaviour as liquids, suggesting there are important underlying principles that connect these seemingly disparate forms of matter. This proposal describes a research program that investigates the structural, thermodynamic and dynamic properties of soft condensed matter systems and aims to address these fundamental questions using molecular theory and computer simulation. In particular, we are focused on understanding how the ability of particles to pack together influences the thermodynamics and dynamics of the liquids. We aim to study how these change when the systems become confined. This will give us insight into how glasses are formed and what factors affect their properties. It will also help us to understand how fluids move in confined systems such as carbon nanotubes and zeolites. We are also interested in nucleation phenomena and plan to develop rigorous theoretical methods for calculating nucleation rates for a range of systems, including the nucleation of complex crystals and nucleation in atmospheric aerosols. While the main focus of the work in this proposal is fundamental in nature, we are using the knowledge gained through our research to explore important applications in technology and nature. For example, we are using our knowledge of the way particles move in confined environments and single file diffusion to develop nanofluidic devices for the separation of mixtures. Also, our studies of nucleation will be used to develop and test accurate theories for the prediction of particle growth and nucleation in atmospheric aerosols, so they can be used in cloud and atmospheric modelling.