电子密度拓扑分析理论方法的拓展研究

Quantum Theory of 'Atoms in molecules' (QTAIM), which is based on the strict quantum mechanics theory, is one of the effective theoretical methods to descript the structures of molecule and crystal. In recent years, the QTAIM theory has been received more and more attention and applied widely in many scientific fields. In this project we will carry out the researches on developing some new models and methods for the topological analysis of electron density in the framework of QTAIM theory. The aims of this project are as follows: by establishing the integral technique of calculating various energy densities in the basins which are classified by the electron location function(ELF) to achieve the topological analysis of the energy density and the Fukui function; by establishing the topological analysis method on the discrete distribution of electron density to give insight into the characteristics of chemical bonds in crystal; by establishing the modols of density difference and density difference stream to realize the energy decomposition in the weak interaction systems and in the formation process of molecule; by investigating the topological properties of chemical bonds in molecules, crystals and reaction process to find out topological indexes of classifying chemical bonds. At the end, we will accomplish a progarm pakage of topological analysis of electron density, GTA2017, which has our own intellectural property rights. The study of this project can provide some new and more effective investigation schemes for theoretical and experimental chemists.

分子中的原子量子理论(QTAIM)是描述分子（晶体）结构的有效理论方法之一，近年来受到广泛的关注和迅速的推广应用。本项目将开展基于QTAIM理论的新模型、新方法研究。建立电子定域函数划分的Basin中各类能量等物理量的积分方法，实现能量密度函数和福井函数的拓扑分析；建立离散密度函数的拓扑分析方法，实现晶体的电子密度拓扑分析；建立并完善密度差函数及密度流模型，实现基于密度差函数的分子相互作用的能量分解方案和分子形成过程中化学键特性的研究；推出拥有自主知识产权的电子密度拓扑分析程序GTA2017，开展分子、晶体和化学反应过程中化学键特征的系统研究，建立新的化学键分类指标。通过本项目的研究为理论化学和实验化学研究提供新的更有效的理论基础和研究方法。

本项目主要研究电子密度拓扑分析新的模型，建立相应的计算方法和程序，并探讨分子、晶体和化学反应过程中化学键的电子密度函数拓扑性质及其变化规律。本项目改进和拓展了现有的电子密度拓扑分析程序，设计了“原子价域”模型和价域内物理量的精确算法。根据原子价域内的各物理量可以更好的描述化学键的强度、性质、极性等参量。建立了离散点局部曲面拟合的计算方法，用于固体中电子密度的拓扑分析。实现了分子生成密度差(MFDD)和跃迁密度差 (TRDD)的计算方法，用于探讨分子形成和状态跃迁过程中分子结构及化学键的变化。进一步完善了反应过程中“结构过渡态”和“结构过渡区”模型，建立了一套判断化学键断裂与生成的拓扑指标体系。推出拥有自主知识产权的电子密度拓扑分析程序GTA2017。应用这些新模型和算法，深入系统地研究了分子、晶体和化学反应中化学键的拓扑性质，如卤键、磷键、硫键以及金属-金属键等。本项目的研究必将为理论化学和实验化学研究提供新的更有效的理论基础和研究方法。