Chemistry and Chemical Biology, Baker Laboratory, Cornell University , Ithaca, New York 14853, United States.
J Am Chem Soc. 2016 Mar 23;138(11):3731-44. doi: 10.1021/jacs.5b12434. Epub 2016 Mar 9.
The energy change per electron in a chemical or physical transformation, ΔE/n, may be expressed as Δχ̅ + Δ(VNN + ω)/n, where Δχ̅ is the average electron binding energy, a generalized electronegativity, ΔVNN is the change in nuclear repulsions, and Δω is the change in multielectron interactions in the process considered. The last term can be obtained by the difference from experimental or theoretical estimates of the first terms. Previously obtained consequences of this energy partitioning are extended here to a different analysis of bonding in a great variety of diatomics, including more or less polar ones. Arguments are presented for associating the average change in electron binding energy with covalence, and the change in multielectron interactions with electron transfer, either to, out, or within a molecule. A new descriptor Q, essentially the scaled difference between the Δχ̅ and Δ(VNN + ω)/n terms, when plotted versus the bond energy, separates nicely a wide variety of bonding types, covalent, covalent but more correlated, polar and increasingly ionic, metallogenic, electrostatic, charge-shift bonds, and dispersion interactions. Also, Q itself shows a set of interesting relations with the correlation energy of a bond.
在化学或物理转化中，每个电子的能量变化ΔE/n 可以表示为Δχ̅ + Δ(VNN + ω)/n，其中Δχ̅是平均电子结合能，广义电负性，ΔVNN 是核排斥能的变化，Δω是所考虑过程中多电子相互作用的变化。最后一项可以通过与第一部分的实验或理论估计值的差值获得。这里将这种能量分配的先前获得的结果扩展到对各种双原子的不同的键合分析中，包括或多或少的极性双原子。提出了将平均电子结合能的变化与共价性相关联的论点，以及将多电子相互作用的变化与电子转移相关联，无论是向分子中转移、向外转移还是在分子内转移。当将新的描述符 Q（基本上是Δχ̅和Δ(VNN + ω)/n 项之间的缩放差异）与键能作图时，它可以很好地区分各种键合类型，包括共价键、更相关的共价键、极性键和越来越离子键、成矿键、静电键、电荷转移键和色散相互作用。此外，Q 本身与键的相关能量也表现出一系列有趣的关系。
