Artificial symmetry breaking in radicals is avoided by the use of the Ensemble-Referenced Kohn-Sham (REKS) method

Michael Filatov, Sason Shaik

Research output: Contribution to journalArticlepeer-review

29 Scopus citations

Abstract

The computational scheme, termed spin-restricted ensemble-referenced Kohn-Sham (REKS) method (M. Filatov, S. Shaik, Chem. Phys. Lett. 304 (1999) 429; M. Filatov, S. Shaik, J. Phys. Chem. A 104 (2000) 6628), developed earlier to treat the strong non-dynamic correlation in singlet diradicals is extended for doublet states of triradicals. The energy and the density in the REKS method are represented as weighted sums of energies and densities of several KS determinants. The new method, dubbed REKS(3,3), is applied to calculation of several model problems where the conventional spin-unrestricted density functional calculations break the spatial symmetry. The results of the REKS(3,3) calculations show that the method avoids an artificial symmetry breaking in open-shell systems.

Original languageEnglish
Pages (from-to)409-419
Number of pages11
JournalChemical Physics Letters
Volume332
Issue number3-4
DOIs
StatePublished - 22 Dec 2000

Fingerprint

Dive into the research topics of 'Artificial symmetry breaking in radicals is avoided by the use of the Ensemble-Referenced Kohn-Sham (REKS) method'. Together they form a unique fingerprint.

Cite this