With the aim of constructing an electronic structure approach that systematically goes beyond the GW and random phase approximation (RPA) we introduce a vertex correction based on the exact-exchange (EXX) potential of time-dependent density functional theory. The EXX vertex function is constrained to be local but is expected to capture similar physics as the Hartree-Fock vertex. With the EXX vertex, we then unify different beyond-RPA approaches such as the various resummations of RPA with exchange and the second-order screened exchange approximation. The theoretical analysis is supported by numerical studies on the hydrogen dimer and the electron gas, and we discuss the role of including the vertex correction in both the screened interaction and the self-energy. Finally, we give details on our implementation within the plane-wave pseudo potential framework and demonstrate the excellent performance of the different RPA with exchange methods in describing the energetics of hydrogen and van der Waals bonds.

Beyond the random phase approximation with a local exchange vertex / Hellgren, Maria; Colonna, Nicola; De Gironcoli, Stefano. - In: PHYSICAL REVIEW. B. - ISSN 2469-9950. - 98:4(2018), pp. 1-12. [10.1103/PhysRevB.98.045117]

Beyond the random phase approximation with a local exchange vertex

Hellgren, Maria
;
Colonna, Nicola;De Gironcoli, Stefano
2018

Abstract

With the aim of constructing an electronic structure approach that systematically goes beyond the GW and random phase approximation (RPA) we introduce a vertex correction based on the exact-exchange (EXX) potential of time-dependent density functional theory. The EXX vertex function is constrained to be local but is expected to capture similar physics as the Hartree-Fock vertex. With the EXX vertex, we then unify different beyond-RPA approaches such as the various resummations of RPA with exchange and the second-order screened exchange approximation. The theoretical analysis is supported by numerical studies on the hydrogen dimer and the electron gas, and we discuss the role of including the vertex correction in both the screened interaction and the self-energy. Finally, we give details on our implementation within the plane-wave pseudo potential framework and demonstrate the excellent performance of the different RPA with exchange methods in describing the energetics of hydrogen and van der Waals bonds.
98
4
1
12
045117
http://harvest.aps.org/v2/bagit/articles/10.1103/PhysRevB.98.045117/apsxml
https://arxiv.org/abs/1804.10566
Hellgren, Maria; Colonna, Nicola; De Gironcoli, Stefano
File in questo prodotto:
File Dimensione Formato  
PRB-98-045117-2018.pdf

non disponibili

Tipologia: Versione Editoriale (PDF)
Licenza: Non specificato
Dimensione 784.79 kB
Formato Adobe PDF
784.79 kB Adobe PDF   Visualizza/Apri   Richiedi una copia
degironcoli_hellgren.pdf

accesso aperto

Tipologia: Documento in Post-print
Licenza: Non specificato
Dimensione 463.13 kB
Formato Adobe PDF
463.13 kB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/20.500.11767/85604
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 22
  • ???jsp.display-item.citation.isi??? 22
social impact