Consequences of approximating electron correlation effects
Consequences of approximating electron correlation effects
复制标题
DOI：
10.1080/00268976.2022.2146540
复制
发表时间：
2022-12-17
影响因子：
1.7
通讯作者：
Cox，Hazel
中科院分区：
文献类型：
--
作者：
Baskerville，Adam L.;Cox，Philippa U.;Cox，Hazel
用三种波函数研究了在少电子系统中近似电子关联的影响：多体波函数（称为完全关联波函数）、Hartree Fock波函数（HF）和Colle和Salvetti Jastrow型波函数（CS），它们用于推导流行的Lee，Yang和Parr（LYP）关联泛函。电子相关能，静态和动态库仑空穴，各种期望值，和径向能量分布（能量密度）被认为是。它表明，虽然CS波函数可以捕获的行为，在库仑势的奇异对应于两个粒子的聚结，并减少了近30%的主要静态库仑孔的面积相比，HF的He和Li，它无法准确地模拟依赖于整个空间的期望值和动态电子密度行为的关键特征，库仑空穴与能量分布中的能量密度行为。当考虑到氢离子和具有用于结合的临界核电荷的系统时，这些问题被放大。
The effect of approximating electron correlation in few-electron systems is investigated using three wavefunctions: the many body wavefunction referred to as fully-correlated (FC), the Hartree Fock wavefunction (HF), and the Colle and Salvetti Jastrow-style wavefunction (CS) used in the derivation of the popular Lee, Yang and Parr (LYP) correlation functional. The electron correlation energy, static and dynamic Coulomb holes, various expectation values, and radial energy distributions (energy densities) are considered. It is shown that whilst the CS wavefunction can capture the behaviour of the wavefunction at the singularities of the Coulomb potential corresponding to the coalescence of two particles and decreases the area of the primary static Coulomb hole by nearly 30% compared to HF for He and Li, it is unable to accurately model expectation values that depend on the whole of space and key features of the electron density behaviour in dynamic Coulomb holes and the energy density behaviour in energy distributions. These issues are amplified when considering the hydride ion and a system with the critical nuclear charge for binding.