Stretched or noded orbital densities and self-interaction correction in density functional theory

Show full item record



Shahi , C , Bhattarai , P , Wagle , K , Santra , B , Schwalbe , S , Hahn , T , Kortus , J , Jackson , K A , Peralta , J E , Trepte , K , Lehtola , S , Nepal , N K , Myneni , H , Neupane , B , Adhikari , S , Ruzsinszky , A , Yamamoto , Y , Baruah , T , Zope , R R & Perdew , J P 2019 , ' Stretched or noded orbital densities and self-interaction correction in density functional theory ' , Journal of Chemical Physics , vol. 150 , no. 17 , 174102 .

Title: Stretched or noded orbital densities and self-interaction correction in density functional theory
Author: Shahi, Chandra; Bhattarai, Puskar; Wagle, Kamal; Santra, Biswajit; Schwalbe, Sebastian; Hahn, Torsten; Kortus, Jens; Jackson, Koblar A.; Peralta, Juan E.; Trepte, Kai; Lehtola, Susi; Nepal, Niraj K.; Myneni, Hemanadhan; Neupane, Bimal; Adhikari, Santosh; Ruzsinszky, Adrienn; Yamamoto, Yoh; Baruah, Tunna; Zope, Rajendra R.; Perdew, John P.
Contributor: University of Helsinki, Department of Chemistry
Date: 2019-05-07
Language: eng
Number of pages: 8
Belongs to series: Journal of Chemical Physics
ISSN: 0021-9606
Abstract: Semilocal approximations to the density functional for the exchange-correlation energy of a many-electron system necessarily fail for lobed one-electron densities, including not only the familiar stretched densities but also the less familiar but closely related noded ones. The Perdew-Zunger (PZ) self-interaction correction (SIC) to a semilocal approximation makes that approximation exact for all one-electron ground- or excited-state densities and accurate for stretched bonds. When the minimization of the PZ total energy is made over real localized orbitals, the orbital densities can be noded, leading to energy errors in many-electron systems. Minimization over complex localized orbitals yields nodeless orbital densities, which reduce but typically do not eliminate the SIC errors of atomization energies. Other errors of PZ SIC remain, attributable to the loss of the exact constraints and appropriate norms that the semilocal approximations satisfy, suggesting the need for a generalized SIC. These conclusions are supported by calculations for one-electron densities and for many-electron molecules. While PZ SIC raises and improves the energy barriers of standard generalized gradient approximations (GGAs) and meta-GGAs, it reduces and often worsens the atomization energies of molecules. Thus, PZ SIC raises the energy more as the nodality of the valence localized orbitals increases from atoms to molecules to transition states. PZ SIC is applied here, in particular, to the strongly constrained and appropriately normed (SCAN) meta-GGA, for which the correlation part is already self-interaction-free. This property makes SCAN a natural first candidate for a generalized SIC. Published under license by AIP Publishing.
116 Chemical sciences

Files in this item

Total number of downloads: Loading...

Files Size Format View
1903.00611.pdf 536.8Kb PDF View/Open

This item appears in the following Collection(s)

Show full item record