Kats Daniel, Köhn Andreas
Max Planck Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany.
Institut für Theoretische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany.
J Chem Phys. 2019 Apr 21;150(15):151101. doi: 10.1063/1.5096343.
The distinguishable cluster approximation applied to coupled cluster doubles equations greatly improves absolute and relative energies. We apply the same approximation to the triples equations and demonstrate that it can also improve the results of the coupled cluster method with singles, doubles, and triples. The resulting method has a nominal computational scaling of O(N) in the real-space representation, and is orbital invariant, size extensive, and exact for three electrons.
应用于耦合簇双激发方程的可区分簇近似极大地改善了绝对能量和相对能量。我们将相同的近似应用于三激发方程，并证明它也能改善含单激发、双激发和三激发的耦合簇方法的结果。所得方法在实空间表示中的名义计算标度为O(N)，具有轨道不变性、尺寸扩展性，并且对三个电子是精确的。
