Malbon Christopher L, Zhao Bin, Guo Hua, Yarkony David R
Department of Chemistry, Johns Hopkins University, Baltimore, MD 21218, USA.
Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, NM 87131, USA.
Phys Chem Chem Phys. 2020 Jun 24;22(24):13516-13527. doi: 10.1039/d0cp01754j.
A four-state diabatic potential energy matrix (DPEM), Hd, for the description of the nonadiabatic quenching of OH(A2Σ+) by collisions with H2 is reported. The DPEM is constructed as a fit to adiabatic energies, energy gradients, and derivative couplings obtained exclusively from multireference configuration interaction wave functions. A four-adiabatic-electronic-state representation is used in order to describe all energetically accessible regions of the nuclear coordinate space. Partial permutation-inversion symmetry is incorporated into the representation. The fit is based on electronic structure data at 42 882 points, described by over 1.6 million least squares equations with a root mean square (mean unsigned) error of 178(83) cm-1. Comparison of ab initio and Hd determined minima, saddle points, and energy minimized points on C2v, Cs, C∞v, and C1 (noncoplanar) portions of two conical intersection seams are used to establish the accuracy of the Hd.
报道了一种用于描述OH(A2Σ+)与H2碰撞非绝热猝灭的四态 diabatic 势能矩阵（DPEM），即Hd。该DPEM是通过对仅从多参考组态相互作用波函数获得的绝热能量、能量梯度和导数耦合进行拟合构建而成。为了描述核坐标空间中所有能量可达区域，采用了四绝热电子态表示。部分置换 - 反演对称性被纳入该表示中。该拟合基于42882个点的电子结构数据，由超过160万个最小二乘方程描述，均方根（平均无符号）误差为178(83) cm-1。通过比较从头算和Hd确定的两个锥形交叉缝的C2v、Cs、C∞v和C1（非共面）部分的极小值、鞍点和能量最小化点，来确定Hd的准确性。
