Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China) and Key Laboratory of Resource Fine-Processing and Advanced Materials of Hunan Province, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha, Hunan 410081, China.
School of Chemical and Biological Engineering, University of Science and Technology Beijing, Beijing, China.
J Chem Phys. 2014 Jan 14;140(2):024109. doi: 10.1063/1.4860969.
Density functional reactivity theory (DFRT) employs the electron density of a molecule and its related quantities such as gradient and Laplacian to describe its structure and reactivity properties. Proper descriptions at both molecular (global) and atomic (local) levels are equally important and illuminating. In this work, we make use of Bader's zero-flux partition scheme and consider atomic contributions for a few global reactivity descriptors in DFRT, including the density-based quantification of steric effect and related indices. Earlier, we proved that these quantities are intrinsically correlated for atomic and molecular systems [S. B. Liu, J. Chem. Phys. 126, 191107 (2007); ibid. 126, 244103 (2007)]. In this work, a new basin-based integration algorithm has been implemented, whose reliability and effectiveness have been extensively examined. We also investigated a list of simple hydrocarbon systems and different scenarios of bonding processes, including stretching, bending, and rotating. Interesting changing patterns for the atomic and molecular values of these quantities have been revealed for different systems. This work not only confirms the strong correlation between these global reactivity descriptors for molecular systems, as theoretically proven earlier by us, it also provides new and unexpected changing patterns for their atomic values, which can be employed to understand the origin and nature of chemical phenomena.
密度泛函反应理论（DFRT）利用分子的电子密度及其相关量，如梯度和拉普拉斯算子，来描述其结构和反应性质。分子（全局）和原子（局部）水平的恰当描述同样重要且具有启发性。在这项工作中，我们利用 Bader 的零通量分区方案，并考虑了 DFRT 中几个全局反应性描述符的原子贡献，包括基于密度的立体效应量化和相关指数。此前，我们已经证明了这些原子和分子系统中的数量是内在相关的[S. B. Liu, J. Chem. Phys. 126, 191107 (2007); ibid. 126, 244103 (2007)]。在这项工作中，我们实现了一种新的基于盆地的积分算法，并广泛检验了其可靠性和有效性。我们还研究了一系列简单的碳氢化合物系统和不同的键合过程场景，包括拉伸、弯曲和旋转。对于不同的系统，这些数量的原子和分子值呈现出有趣的变化模式。这项工作不仅证实了我们之前从理论上证明的分子系统中这些全局反应性描述符之间的强相关性，还为它们的原子值提供了新的、意想不到的变化模式，可用于理解化学现象的起源和本质。
