Andrada Diego M, Foroutan-Nejad Cina
Faculty of Natural Sciences and Technology, Department of Chemistry, Saarland University, 66123 Saarbrücken, Federal Republic of Germany.
Phys Chem Chem Phys. 2020 Oct 15;22(39):22459-22464. doi: 10.1039/d0cp04016a.
Here, we discuss that unlike bond dissociation energy (BDE) that is a state function quantity, the energy components of the energy decomposition analysis (EDA), i.e. electrostatic interaction, Pauli repulsion, and orbital interaction, are path (process) function quantities. Being a path function means that EDA energy components are not uniquely defined, i.e. the relative magnitudes of the orbital interaction, Pauli repulsion, and electrostatic components may vary depending on the selected pathway for EDA. Therefore, at best, EDA can define whether closely related chemical bonds are more or less ionic/covalent compared with each other. However, a precise assessment of the nature of a certain type of chemical bond using EDA is a questionable task. Besides, we briefly discuss that the widely used EDA pathway, which is merely an arbitrary choice among infinite possible paths, comes to conclusions not consistent with our widely accepted knowledge of bond formation even for the simplest molecules.
在此,我们讨论与作为状态函数量的键解离能(BDE)不同,能量分解分析(EDA)的能量成分,即静电相互作用、泡利排斥和轨道相互作用,是路径(过程)函数量。作为路径函数意味着EDA能量成分不是唯一确定的,即轨道相互作用、泡利排斥和静电成分的相对大小可能会根据所选的EDA路径而变化。因此,EDA充其量只能确定与彼此相比,紧密相关的化学键在离子性/共价性方面是更强还是更弱。然而,使用EDA精确评估某类化学键的性质是一项有问题的任务。此外,我们简要讨论了广泛使用的EDA路径,它仅仅是无限可能路径中的任意选择,即使对于最简单的分子,其得出的结论也与我们广泛接受的键形成知识不一致。