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Functional *N*-Representability in 2-Matrix, 1-Matrix, and Density Functional Theories

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*N*-representability conditions on the reduced second-order reduced density matrix (2-RDM), impose restrictions not only in the context of reduced density matrix theory (RDMT), but also on functionals advanced in one-matrix theory such as natural orbital functional theory (NOFT), and on functionals depending on the one-electron density such as those of density functional theory (DFT). We review some aspects of the applications of these*N*-representability conditions in these theories and present some conclusions.Conflicts of Interest

The authors declare no conflicts of interest.

Cite this paper

E. Ludeña, F. Torres and C. Costa, "Functional

*N*-Representability in 2-Matrix, 1-Matrix, and Density Functional Theories,"*Journal of Modern Physics*, Vol. 4 No. 3A, 2013, pp. 391-400. doi: 10.4236/jmp.2013.43A055.

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