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arXiv 2102.12992physics.chem-phquant-ph
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减小密度泛函理论的电荷离域误差

Reducing charge delocalization error of density functional theory

Emil Proynov, Jing Kong

摘要:

除了非动力学关联外,电荷离域误差一直是密度泛函理论面临的主要挑战。当代泛函低于对称带电二聚体A2+的解离,这是一个简单但严格的测试,预测了一个虚假的势垒,并不正确地使带电分子团簇的电荷离域。我们扩展了一个功能设计的非动态相关治疗电荷离域误差通过修改平行自旋的非动态相关。修正后的泛函消除了这些问题,减小了多电子自相互作用误差。与当代泛函相比,它的结果与CCSD(T)的结果在整个分离范围内是最接近的。它正确地定位净正电荷在(CH 4)n+团簇,并预测一个几乎恒定的电离势的结果。SIE4x4集的测试表明,新功能优于文献中针对该集评估的各种功能。总体而言,我们表明治疗电荷离域与非动态相关的可行性。

英文摘要:

The charge delocalization error, besides nondynamic correlation, has been a major challenge to density functional theory. Contemporary functionals undershoot the dissociation of symmetric charged dimers A2+, a simple but stringent test, predict a spurious barrier and improperly delocalize charges for charged molecular clusters. We extend a functional designed for nondynamic correlation to treat the charge delocalization error by modifying the nondynamic correlation for parallel spins. The modified functional eliminates those problems and reduces the multielectron self-interaction error. Furthermore, its results are the closest to those of CCSD(T) in the whole range of the dissociation compared with contemporary functionals. It correctly localizes the net positive charge in (CH4)n+ clusters and predicts a nearly constant ionization potential as a result. Testing of the SIE4x4 set shows that the new functional outperforms a wide variety of functionals assessed for this set in the literature. Overall, we show the feasibility of treating charge delocalization together with nondynamic correlation.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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