Department of Chemistry and Chemical Engineering, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing, 100083, People's Republic of China; Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline Materials, Beijing, 100083, People's Republic of China.
J Comput Chem. 2014 Jan 15;35(2):121-9. doi: 10.1002/jcc.23471. Epub 2013 Nov 7.
A new multireference perturbation series is derived based on the Rayleigh-Schrödinger perturbation theory. It is orbitally invariant. Its computational cost is comparable to the single reference Møller-Plesset perturbation theory. It is demonstrated numerically that the present multireference second- and third-order energies are size extensive by two types of supermolecules composed of H2 and BH monomers. Spectroscopic constants of F2(X1Σg+),Cl2(X1Σg+),C2-(X2Σg+),B2(X3Σg-),and C2+(X4Σg-) as well as the ground state energies of H2O, NH2, and CH2 at three bond lengths have been calculated with the second multireference perturbation theory. The dissociation behaviors of CH4 and HF have also been investigated. Comparisons with other approximate theoretical models as well as the experimental data have been carried out to show their relative performances.
基于瑞利-薛定谔微扰理论推导出了一个新的多参考微扰级数。它是轨道不变的。其计算成本与单参考 Møller-Plesset 微扰理论相当。通过由 H2 和 BH 单体组成的两种超分子，数值证明了目前的多参考二阶和三阶能量是大小扩展性的。计算了 F2(X1Σg+)、Cl2(X1Σg+)、C2-(X2Σg+)、B2(X3Σg-)和 C2+(X4Σg-)的光谱常数以及 H2O、NH2 和 CH2 在三个键长下的基态能量。还研究了 CH4 和 HF 的离解行为。与其他近似理论模型以及实验数据进行了比较，以显示它们的相对性能。
