使用对波函数进行一阶修正的抽样的选定组态相互作用方法。

Selected configuration interaction method using sampled first-order corrections to wave functions.

机构信息

Institute for Catalysis, Hokkaido University, N21 W10 Kita-ku, Sapporo, Hokkaido 001-0021, Japan.

出版信息

J Chem Phys. 2017 Jul 21;147(3):034102. doi: 10.1063/1.4993214.

Abstract

A new selected configuration interaction (CI) method was proposed for the potential energy surfaces of quasi-degenerate and excited states. Slater determinants are generated by sampling the first-order corrections to the target-state wave functions using the quantum Monte Carlo method in determinant space. As in the Monte Carlo (MC) CI method, the wave function is improved at each iteration by generating new determinants and applying a pruning step. Compared to the random generation in the MCCI calculations, the number of iterations before convergence is significantly reduced. Regarding the potential energy curves of the ground and excited states of C, the non-parallelity errors were sufficiently small, thus indicating the method's applicability to the calculations of potential energy surfaces.

摘要

提出了一种新的选择组态相互作用（CI）方法，用于准简并和激发态的位能表面。Slater 行列式通过在行列式空间中使用量子蒙特卡罗方法对目标态波函数的一阶修正进行抽样来生成。与 MC CI 方法一样，在每次迭代时，通过生成新的行列式并应用修剪步骤来改进波函数。与 MCCI 计算中的随机生成相比，收敛前的迭代次数显著减少。对于 C 的基态和激发态的位能曲线，非平行性误差足够小，表明该方法适用于位能表面的计算。