GOALI: Development of Transferable Force Fields for Phase Equilibria

摘要-9813601 J。I. Seipmann/U.明尼苏达州戈利：相平衡可转移力场的发展所提出的研究的目标是为大范围的有机分子和水设计两个级别的可转移力场。 第一个层次，称为TrapPE（相平衡的可转移势），采用联合原子表示法和简单的Lennard-Jones和库仑项。 在第二个层次中，称为TrapPE-pol（可极化），所有原子都被明确建模，货车德瓦尔斯和静电相互作用都可以响应环境的变化。 第一级是为了简单和计算效率以及良好的准确性而设计的，而第二级的目标仅仅是尽可能高的准确性和可转移性。 这些力场将使我们能够研究单组分和多组分的相平衡，混合的过量性质，并预测分配系数和分离因子。 可转移的力场将包括直链、支链和环状烷烃、烯烃、炔、醇、醚、酮、羧酸、烷基苯，最后但并非最不重要的是，水。除了力场的发展，该提案还提出了新的模拟算法，其目标是有效模拟含有非常极性和/或氢键物种的混合物，这将允许对可极化力场进行有效的蒙特卡罗采样。 使用可转移力场的分子模拟将被用作工程工具来预测各种系统的热物理性质，从而增加实验数据库。 模拟将为复杂的化学系统提供丰富的微观层面的信息，从而为分子结构和组成如何决定宏观现象提供新的物理见解。这个跨学科的项目将受益于具有不同知识，专业知识和观点的人们的广泛合作。 一方面，一个由PI和乔治帕克斯博士和菲利普斯石油公司的威廉帕里什组成的紧密的大学-工业团队将推进该项目。 另一方面，特拉华州大学的斯坦利·桑德勒博士将从一位经验丰富的实验性质工作者的角度提供额外的指导。

ABSTRACTCTS-9813601J. I. Seipmann/U. of Minn.GOALI: Development of Transferable Force Fields for Phase EquilibriaThe goal of the proposed research is to design two levels of transferable force fields for a large spectrum of organic molecules and water. The first level, called TraPPE (Transferable Potentials for Phase Equilibria),employs the united-atom representation and simple Lennard-Jones and Coulombic terms. In the second level, called TraPPE-pol (polarizable), all atoms are modeled explicitly, and both the van der Waals and electrostatic interactions can respond to changes in the environment. Whereas the first level is, designed for simplicity and computational efficiency with good accuracy, the second level is aimed solely at the highest possible accuracy and transferability. These force fields will allow us to study single and multi-component phase equilibria, excess properties of mixing, and to predict partition coefficients and separationfactors. The transferable force fields will encompass linear, branched, and cyclic alkanes, alkenes, alkynes, alcohols, ethers, ketones, carboxylic acids, alkylbenzenes, and last, but not least, water.In addition to the force field development, this proposal also addresses novel simulation algorithms which are targeted at efficient simulations of mixtures containing very polar and/or hydrogen-bonding species, and which will allow efficient Monte Carlo sampling for polarizable force fields. Molecular simulations using the transferable force fields will be employed as engineering tool to predict thermophysical properties of a variety of systems, thereby adding to the experimental database. The simulations will providea wealth of microscopic-level information for complex chemical systems, thereby giving new physical insight into how molecular architecture and composition determine macroscopic phenomena.This interdisciplinary project will profit from extensive collaboration of people with different knowledge, expertise, and perspective. On the one side, a tight university-industry team consisting of the PI and Drs. George Parks and William Parrish of Phillips Petroleum will advance the project. On the other side, Dr. Stanley Sandler, Univ. of Delaware, will provide additional guidance from the viewpoint of an experienced experimental properties worker.