Nonadditivity in Molecular Interactions

该项目由理论与计算化学 计划将研究在各种分子间相互作用的非加性 使用第一原理从头计算量子力学方法的化学系统。 弱的分子间力和相互作用在 对凝聚态物质性质的研究。在这样的环境下， 的相互作用 会影响它们与一对分子相互作用的方式， 三分之 因此，分子间相互作用的两两相加的假设是一个非常差的近似。 目前大多数模拟凝聚相反应的方法要么完全忽略相互作用的非加和性，要么试图以非常粗略的方式将其包括在内，并在相互作用势中混入许多错误。 关于非加性的一个常见误解是，它源于单一来源。 然而，实际上，它是由许多根本不同的物理现象产生的。 本理论研究旨在阐明所有的影响 负责非加和性，并将其分解为 标记 扩散、诱导和交换。 这样的分析将导致 从根本上提高对这些影响的认识。这项工作将 导致了一些分析潜力的发展， 包括多体效应，因此适用于模拟凝聚态 阶段。作为 以及簇的性质。

This project supported by the Theoretical and Computational Chemistry program will study non-additivity of intermolecular interactions in a variety of chemical systems using first principles ab-initio quantum mechanical methods. Weak intermolecular forces and interactions are of key importance in studies of the properties of matter in condensed phases. In such an environment, the interaction in a pair of molecules affects the ways each of them interacts with a third. The assumption of pairwise additivity of intermolecular interactions is thus a very poor approximation. Most current means of simulating condensed phase reactions either disregard non-additivity of interactions entirely, or attempt to include it in a very crude manner, mixed together with a number of errors in the interaction potentials. One common misconception about non-additivity is that it originates from a single source. However, in reality it arises from a number of fundamentally different physical phenomena. This theoretical research is aimed at elucidating all of the effects responsible for non-additivity and to break these down into components which are labeled dispersion, induction and exchange. Such an analysis will lead to an improved understanding of these effects on a fundamental level. This work will result in the development of a number of analytical potentials which explicitly include many-body effects and are thus suitable for simulations of condensed phases. as well as properties of clusters.