International Workshop on 'New challenges in Reduced Density Matrix Functional Theory: Symmetries, time-evolution and entanglement'
Recent advances in NOF theoryIon Mitxelena
University of the Basque Country UPV/EHU
Coauthor(s) : M. Piris
 Donostia International Physics Center (DIPC), 20018 Donostia, Euskadi, Spain
General expressions for analytic gradients with respect to nuclear motion are derived for NOFT [1,2], in such a way that resulting equations do not require resorting to linear-response theory. Recently published PNOF7  is used to yield accurate equilibrium geometries in agreement with experimental data. The latter is also tested by using the 2-, 4- and 6-sites Hubbard model, together with a set of commonly used NOFs [4,5]. Encouraging results point out the importance of imposing (2,2)-positivity N-representability conditions on the 2-RDM  in order to obtain accurate and consistent results, as well as the balanced treatment of static and dynamic electron correlation.
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