Ren Mingxing, Liu Xin, Zhang Lina, Lin Xuhui, Wu Wei, Chen Zhenhua
The State Key Laboratory of Physical Chemistry of Solid Surfaces, Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China.
J Chem Phys. 2022 Aug 28;157(8):084106. doi: 10.1063/5.0097614.
This paper combines the valence bond block diabatization approach with the idea of orbital breathing. With highly compact wave functions, the breathing orbital valence bond (BOVB) method is applied to investigate several atomic and molecular properties, including the electron affinity of F, the adiabatic and diabatic potential energy curves and the dipole moment curves of the two lowest-lying Σ states, the electronic coupling curve and the crossing distance of the two diabatic states, and the spectroscopic constants of the ground states for LiF. The configuration selection scheme proposed in this work is quite general, requiring only the selection of several de-excitation and excitation orbitals in a sense like the restricted active space self-consistent field method. Practically, this is also the first time that BOVB results are extrapolated to complete basis set limit. Armed with the chemical intuition provided by valence bond theory, the classic but challenging covalent-ionic interaction in the title molecule is not only conceptually interpreted but also accurately computed.
本文将价键块对角化方法与轨道呼吸的概念相结合。利用高度紧凑的波函数，应用呼吸轨道价键（BOVB）方法研究了几种原子和分子性质，包括氟的电子亲和能、两个最低的Σ态的绝热和非绝热势能曲线及偶极矩曲线、两个非绝热态的电子耦合曲线和交叉距离，以及氟化锂基态的光谱常数。本工作中提出的构型选择方案非常通用，在某种意义上，只需要像受限活性空间自洽场方法那样选择几个去激发和激发轨道。实际上，这也是首次将BOVB结果外推到完全基组极限。借助价键理论提供的化学直觉，不仅从概念上解释了标题分子中经典但具有挑战性的共价 - 离子相互作用，而且还对其进行了精确计算。
