Alternative linear-scaling methodology for the second-order Moller-Plesset perturbation calculation based on the divide-and-conquer method

A new scheme for obtaining the approximate correlation energy in the divide-and-conquer (DC) method of Yang [Phys. Rev. Lett. 66, 1438 (1991)] is presented. In this method, the correlation energy of the total system is evaluated by summing up subsystem contributions, which are calculated from subsystem orbitals based on a scheme for partitioning the correlation energy. We applied this method to the second-order Moller-Plesset perturbation theory (MP2), which we call DC-MP2. Numerical assessment revealed that this scheme provides a reliable correlation energy with significantly less computational cost than the conventional MP2 calculation. (c) 2007 American Institute of Physics.

提出了一种在杨（Yang）的分治法（DC）中获取近似相关能的新方案[《物理评论快报》66卷，1438页（1991年）]。在此方法中，通过累加子系统的贡献来计算整个系统的相关能，这些子系统贡献是基于一种划分相关能的方案，由子系统轨道计算得出。我们将此方法应用于二阶莫勒 - 普莱斯（Møller - Plesset）微扰理论（MP2），我们称之为DC - MP2。数值评估表明，该方案提供了可靠的相关能，且计算成本比传统的MP2计算显著降低。（c）2007美国物理学会。