Takeshita Tyler Y, de Jong Wibe A, Neuhauser Daniel, Baer Roi, Rabani Eran
Department of Chemistry, University of California Berkeley , Berkeley, California 94720, United States.
Materials Sciences Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States.
J Chem Theory Comput. 2017 Oct 10;13(10):4605-4610. doi: 10.1021/acs.jctc.7b00343. Epub 2017 Sep 15.
A stochastic orbital approach to the resolution of identity (RI) approximation for 4-index electron repulsion integrals (ERIs) is presented. The stochastic RI-ERIs are then applied to second order Møller-Plesset perturbation theory (MP2) utilizing a multiple stochastic orbital approach. The introduction of multiple stochastic orbitals results in an O(N) scaling for both the stochastic RI-ERIs and stochastic RI-MP2, N being the number of basis functions. For a range of water clusters we demonstrate that this method exhibits a small prefactor and observed scalings of O(N) for total energies and O(N) for forces (N being the number of correlated electrons), outperforming MP2 for clusters with as few as 21 water molecules.
提出了一种用于求解四指标电子排斥积分（ERI）恒等式（RI）近似的随机轨道方法。然后，利用多重随机轨道方法将随机RI-ERI应用于二阶Møller-Plesset微扰理论（MP2）。多重随机轨道的引入使得随机RI-ERI和随机RI-MP2的计算量均按O(N)缩放，其中N为基函数的数量。对于一系列水团簇，我们证明该方法具有较小的前置因子，总能量的计算量按O(N)缩放，力的计算量也按O(N)缩放（N为相关电子的数量），对于仅有21个水分子的团簇，其性能优于MP2。
