Using complex degrees of freedom in the Kohn-Sham self-interaction correction

被引：49

作者：

Hofmann, D. ^{[1
]}

Kluepfel, S. ^{[2
]}

Kluepfel, P. ^{[2
]}

Kuemmel, S. ^{[1
]}

机构：

[1] Univ Bayreuth, D-95440 Bayreuth, Germany

[2] Univ Iceland, Inst Sci, VR 3, IS-107 Reykjavik, Iceland

来源：

PHYSICAL REVIEW A | 2012年 / 85卷 / 06期

关键词：

DENSITY-FUNCTIONAL THEORY; ELECTRONIC-STRUCTURE CALCULATIONS; AB-INITIO; MOLECULAR ORBITALS; INTERACTION ERROR; GROUND-STATE; APPROXIMATION; EXCHANGE; LOCALIZATION; PREDICTION;

D O I：

10.1103/PhysRevA.85.062514

中图分类号：

O43 [光学];

学科分类号：

070207 ; 0803 ;

摘要：

The Perdew-Zunger self-interaction correction (SIC) to local and semilocal density functionals systematically underestimates molecular bond lengths, yet improves many other ground-state properties. An alternative definition of a SIC is reached by using the Perdew-Zunger energy with a global, multiplicative Kohn-Sham potential instead of the orbital-specific potentials of traditional SIC. Due to the unitary variance of the SIC energy, the most general construction of the SIC Kohn-Sham potential involves a unitary transformation of the Kohn-Sham orbitals. We systematically investigate the Kohn-Sham version of the SIC, in particular with respect to the bond-length question, and present a detailed analysis of the influence of different unitary transformations. Using a complex-valued energy-minimizing transformation appears to be the most favorable approach, and we explain this result by analyzing orbital densities. We discuss how to calculate the transformations efficiently.

引用

页数：11

共 85 条

[31] Density-functional study of small molecules within the Krieger-Li-Iafrate approximation [J].