Inhomogeneous random-phase approximation and many-electron trial wave functions
Inhomogeneous random-phase approximation and many-electron trial wave functions
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非齐次随机相位近似和多电子试验波函数
DOI：
10.1103/physrevb.63.115115
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发表时间：
2001
期刊：
影响因子：
--
通讯作者：
G. Rajagopal
中科院分区：
文献类型：
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作者：
R. Gaudoin;M. Nekovee;W. Foulkes;R. Needs;G. Rajagopal
均匀电子气中的长程电子关联可以由无规相位近似~RPA！of Bohm and Pines @Phys. Rev. 92，609 ~1953！#.在这里，我们将RPA推广到非均匀系统，并使用它来推导量子蒙特卡罗模拟的多电子斯莱特-杰斯特罗试验波函数。RPA理论修正了Jastrow因子中非齐次二体项的长程行为，并为单体项提供了精确的解析表达式。它还解释了斯莱特-杰斯特罗试验函数的成功，其中包含哈特里-福克或密度泛函轨道的决定因素，即使这些理论不包括杰斯特罗因子。在调整RPA Jastrow因子以纳入已知的短程行为后，我们使用变分Monte Carlo模拟对其进行测试。在小的非均匀电子气系统，我们认为，基于RPA的Jastrow因子的分析略优于标准的数值优化形式。因此，非齐次RPA理论使我们能够减少甚至避免昂贵的数值优化过程。
The long-range electronic correlations in a uniform electron gas may be deduced from the random-phase approximation ~RPA! of Bohm and Pines @Phys. Rev. 92, 609 ~1953!#. Here we generalize the RPA to nonuniform systems and use it to derive many-electron Slater-Jastrow trial wave functions for quantum Monte Carlo simulations. The RPA theory fixes the long-range behavior of the inhomogeneous two-body terms in the Jastrow factor and provides an accurate analytic expression for the one-body terms. It also explains the success of Slater-Jastrow trial functions containing determinants of Hartree-Fock or density-functional orbitals, even though these theories do not include Jastrow factors. After adjusting the RPA Jastrow factor to incorporate the known short-range behavior, we test it using variational Monte Carlo simulations. In the small inhomogeneous electron gas system we consider, the analytic RPA-based Jastrow factor slightly outperforms the standard numerically optimized form. The inhomogeneous RPA theory therefore enables us to reduce or even avoid the costly numerical optimization process.