Understanding the Role of Dispersion Interactions in the Mechanical Properties of Molecular Crystals

分子材料在科学和工业中具有重要的基础和应用意义，在制药、食品科学、电子、传感和催化等领域有着广泛的应用。分子晶体的力学性能是近年来在实验中受到特别关注的一个领域。对分子晶体机械反应的理解和预测能力将对制药业（片剂药物配方）、有机电子学（柔性和导电材料）和高能材料产生深远的影响。虽然已经提出了许多这些应用和现象，但它们尚未得到很好的理解，并且没有建立分子晶体的结构/性质关系。该项目的主要目标是从第一性原理中更深入地了解分子晶体的机械特性，特别侧重于了解范德华色散相互作用在这些特性中的作用。该过程的第一步是对具有良好实验数据的一系列模型系统的弹性特性进行探测。将这些数据与使用不同层次理论的计算预测进行比较，将使我们能够理解哪种方法对更复杂的系统建模是必要的。该项目的第二阶段将重点关注“机械化学”应用的两个关键领域：药品和柔性材料。该项目将有助于从理论和实践两方面了解分子晶体的力学性质。首先，我们将确定准确研究分子晶体对外部扰动的响应所必需的理论描述水平。其次，我们将研究当前非常感兴趣的系统，为新型药物和柔性材料的设计和开发开辟新的方向。

Molecular materials are of great fundamental and applied importance in science and industry, with numerous applications in pharmaceutics, food science, electronics, sensing, and catalysis. The mechanical properties of molecular crystals is an area that has received particular experimental attention in recent years. The understanding and ability to make prediction of the mechanical response of molecular crystals would have far reaching consequences for the pharmaceutical industry (formulation of drugs in tablets), organic electronics (flexible and conducting materials), and energetic materials. While many of these applications and phenomena have been proposed, they are not yet well understood and there are no established structure/property relations for molecular crystals.The primary objective of the project is to gain a deeper understanding of the mechanical properties of molecular crystals from first principles, with particular focus on understanding the role of van der Waals dispersion interactions on these properties. The first step in this process is to probe the elastic properties for a series of model systems that have good experimental data. Comparison of these data with computational predictions, using various levels of theory, will enable us to understand which approach is necessary to model more complex systems. The second stage of the project will focus on two key areas of application of "mechanochemistry": pharmaceuticals and flexible materials.This project will contribute to both the theoretical and practical understanding of mechanical properties of molecular crystals. Firstly, we will identify the level of theoretical description necessary to accurately study the response of molecular crystals to external perturbations. Secondly, we will study systems of great current interest, opening new directions in the design and development of novel pharmaceuticals and flexible materials.