IQA analysis of the two-particle density matrix: chemical insight and computational efficiency
IQA analysis of the two-particle density matrix: chemical insight and computational efficiency
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DOI：
10.1007/s00214-023-03057-x
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发表时间：
2023-11-01
影响因子：
1.7
通讯作者：
Popelier，Paul L. A.
中科院分区：
文献类型：
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作者：
Vincent，Mark A.;Popelier，Paul L. A.
相互作用量子原子(IQA)方法提供了一种从两粒子密度矩阵(2Pdm)计算原子电子关联能的严格和最小的途径。付出的代价是，这种方法非常耗时。然而，使用CCSD和CCSD(T)，我们探索了几种加速此类计算的方法。我们做了一个关键的观察，从真正的2PDM中去掉了2PDM的Hartree-Fock部分和近似的2PDM(Müler)，大大减少了获得精确能量所需的正交网格的大小。
The interacting quantum atoms (IQA) method offers a rigorous and minimal route to calculate atomic electron correlation energies from the two-particle density matrix (2PDM). The price paid is that this method is very time-consuming. However, employing CCSD and CCSD(T), we explore several approaches to speed up such calculations. We make the pivotal observation that the removal, from the true 2PDM, of both the Hartree–Fock part of the 2PDM and an approximate 2PDM (Müller) dramatically reduces the size of the quadrature grid needed to obtain accurate energies.