Quantum-Designed Models of Bulk and Interfacial Solvation

辛辛那提大学的托马斯贝克得到了化学系化学理论、模型和计算方法项目的支持，以开发新的理论和计算方法，更好地理解复杂的液体混合物。 贝克和他的研究小组开发并使用先进的计算机模拟来研究分子如何相互作用，以产生生物，工业化学，家用化学品（如肥皂）和电池材料中的巨大复杂性。 他们使用这些先进的方法来模拟水中和水面附近各种带电粒子（离子）的基本特性。 他们还将这些技术扩展到研究锂离子电池中使用的有机液体中的离子。 此外，Beck小组采用新的计算方法来模拟与工业化学过程相关的液体混合物的相分离。 准确性很重要，因为描述分子间相互作用的力场的微小变化往往会导致混合物完全不同的理论行为。 更深入地了解相互作用和由此产生的系统特性，例如，开发更高效和更安全的电池材料。 将这一基础科学传播给更广泛的社区越来越重要，贝克在辛辛那提博物馆中心负责一个项目，该项目将培养10名博士。他的部门的学生在博物馆的地板上进行有效的科学演示。溶剂化和界面现象是各种物理，化学和生物系统的核心，包括纳米材料，表面活性剂，合成化学，膜，蛋白质和能源科学。虽然在开发复杂离子和分子混合物和界面的精确模型方面取得了重大进展，但在建立溶剂化的预测科学方面仍然存在重大挑战。这项赠款的主要目标有三个。 贝克小组进行了广泛的从头算量子分子动力学模拟，结合先进的统计力学理论，建立了水中基本的单离子自由能标度，并探索了有机溶剂中离子溶剂化的基本结构和动力学。 该团队利用从头算模拟的数据构建了新的量子设计模型，该模型包含了溶剂化的基本物理成分。 他们还将这些新模型应用于具有挑战性的系统，例如预测液-液平衡和竞争性溶剂与复杂分子混合物中离子的结合。采用的理论方法包括分布电荷多极模型和Drude振荡器优化与进化算法来模拟电子分布的凝聚相量子模拟数据。由此产生的预测计算模型被用于界面静电的研究，在解决方案和近界面的特定离子效应，并在用于能量存储设备和绿色化学过程中的有机溶剂中的离子溶剂化研究。该奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

Thomas Beck of the University of Cincinnati is supported by an award from the Chemical Theory, Models and Computational Methods program in the Division of Chemistry to develop new theoretical and computational methods to better understand complex liquid mixtures. Beck and his research group develop and use advanced computer simulations to investigate how molecules interact with each other to produce the great complexity in living things, industrial chemistry, household chemicals such as soaps, and battery materials. They use these advanced methods to model the basic properties of various charged particles (ions) in water and near the water surface. They also extend these techniques to studies of ions in organic liquids that are used in lithium ion batteries. In addition, the Beck group employs the new calculations to model phase separation in liquid mixtures relevant to industrial chemical processes. Accuracy is important because slight changes in the force fields that describe interactions between molecules often lead to completely different theoretical behaviors of the mixture. Gaining more insight into the interactions and resulting system properties results, for example, in the development of more efficient and safer battery materials. Communicating this basic science to the broader community is increasingly important, and Beck oversees a program at the Cincinnati Museum Center that will train 10 Ph.D. students from his Department to engage in effective science demonstrations on the floor of the museum. Solvation and interfacial phenomena are central to a diverse array of physical, chemical, and biological systems including nanomaterials, surfactants, synthetic chemistry, membranes, proteins, and the energy sciences. While significant progress has been made in developing accurate models of complex ionic and molecular mixtures and interfaces, major challenges remain in building a predictive science of solvation. The principal objectives of this grant are threefold. The Beck group performs extensive ab initio quantum molecular dynamics simulations coupled with advanced statistical mechanical theories that establish a fundamental single-ion free energy scale in water and that explores the basic structure and dynamics of ion solvation in organic solvents. The team utilizes data from the ab initio simulations in constructing novel quantum-designed models that incorporate the essential physical components of solvation. They also applying these new models to challenging systems such as predicting liquid-liquid equilibrium and competitive solvent binding to ions in complex molecular mixtures. The theoretical methods employed include distributed charge multipole models and Drude oscillators optimized with evolutionary algorithms to mimic the electronic distributions in the condensed phase quantum simulation data. The resulting predictive computational models are employed in studies of interfacial electrostatics, specific ion effects in solution and near interfaces, and in ion solvation studies in organic solvents used in energy storage devices and in green chemistry processes.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.