Using on-top pair density for construction of correlation functionals for multideterminant wave functions
2004 (English)In: Molecular Physics, ISSN 0026-8976, E-ISSN 1362-3028, Vol. 102, no 21-22, 2207-2216 p.Article in journal (Refereed) Published
The value of the two-particle density function at coalescence P-2(ontop)(r) = rho(2)(r, r) is frequently used as an additional variable for formulating approximate exchange-correlation or correlation functionals. Here, its applications as one of the key variables for the construction of new DFT (preferably multi-determinant) functionals is investigated. The basic formalism is presented and it is shown that this replacement avoids some difficulty to construct a Fock matrix in a ROKS (restricted open-shell Kohn-Sham) method and also to reduce the ‘double counting’ of correlation energy in CASDFT (complete active space density functional theory) calculations. Calculations of excitation energies for transition metals and dissociation curves for diatomic molecules are presented as an example.
Place, publisher, year, edition, pages
2004. Vol. 102, no 21-22, 2207-2216 p.
IdentifiersURN: urn:nbn:se:uu:diva-143901DOI: 10.1080/00268970410001734297OAI: oai:DiVA.org:uu-143901DiVA: diva2:394364
European Network THEONET II Meeting, Bologna, ITALY, NOV, 20032011-02-022011-01-252015-01-08Bibliographically approved