论文标题
三阶Møller-plesset理论使其更有用？密度功能理论轨道的作用
Third order Møller-Plesset theory made more useful? The role of density functional theory orbitals
论文作者
论文摘要
Møller-plesset（MP）扰动理论的实际实用性受到使用Hartree-Fock（HF）轨道的严重限制。最近已经显示，使用正则化轨道优化的MP2轨道以及MP3能量的缩放可能导致MP3误差的显着降低（J. Phys。Chem。Lett。10，4170，2019）。在这项工作中，我们检查了是否可以同样使用密度功能理论（DFT）优化的轨道来提高MP理论在MP2和MP3水平上的性能。我们发现，与基于标准HF的MP理论相对于热化学，屏障高度，非共价相互作用和偶极矩的预测，使用DFT轨道可显着提高性能。实际上，发现具有DFT轨道的MP3（或不带缩放）超过了几个数据集的耦合群集单打和双打（CCSD）的准确性。我们还发现，在大多数情况下，结果并不是特别敏感的（尽管范围分离的混合功能低得多的误差误差表现最好）。因此，基于DFT轨道的MP3似乎是单参引用电子结构计算的有效的，非介绍性$ O（n^6）$缩放波函数方法。在许多情况下，还发现具有DFT轨道的缩放MP2非常准确，尽管现代的双杂交功能可能更准确。
The practical utility of Møller-Plesset (MP) perturbation theory is severely constrained by the use of Hartree-Fock (HF) orbitals. It has recently been shown that use of regularized orbital-optimized MP2 orbitals and scaling of MP3 energy could lead to a significant reduction in MP3 error (J. Phys. Chem. Lett. 10, 4170, 2019). In this work we examine whether density functional theory (DFT) optimized orbitals can be similarly employed to improve the performance of MP theory at both the MP2 and MP3 levels. We find that use of DFT orbitals leads to significantly improved performance for prediction of thermochemistry, barrier heights, non-covalent interactions, and dipole moments relative to standard HF based MP theory. Indeed MP3 (with or without scaling) with DFT orbitals is found to surpass the accuracy of coupled cluster singles and doubles (CCSD) for several datasets. We also found that the results are not particularly functional sensitive in most cases, (although range-separated hybrid functionals with low delocalization error perform the best). MP3 based on DFT orbitals thus appears to be an efficient, non-iterative $O(N^6)$ scaling wave function approach for single-reference electronic structure computations. Scaled MP2 with DFT orbitals is also found to be quite accurate in many cases, although modern double hybrid functionals are likely to be considerably more accurate.
