A view of outstanding problems in density functional theory

Wednesday, October 8, 2008 - 10:00am - 11:00am
Lind 409
Steven Valone (Los Alamos National Laboratory)
Constrained-search density functional theory (DFT) pioneered by Levy [1] poses the problem of the theory as one of searching over subsets of Hilbert space. As such it provides a hypothetical means of constructing density-based energy functionals for use in electronic structure applications. I will illustrate the constrained-search form with simple examples [2]. Early results on continuity of the energy functional [3] and the advent of open-system DFT [4] will be reviewed. The construction of energy functionals will discussed in the context of the Colle-Salvetti functionals [5] that played a subtle, but important, role in the 1998 Nobel Prize in Chemistry [6]. Alternative constructions based on constrained-search DFT will be discussed. Finally topics pertaining to excitations in homogeneous electron gases and from the introduction of other constraints to DFT calculations [7,8] will be entertained.

[1] M Levy, Proc Natl Acad Sci USA 76, 6062 (1979).
[2] SM Valone, Vignette on Constrained-Search Density Functional Theory, private communication, August (2008).
[3] SM Valone, J Chem Phys 73, 1344 (1980).
[4] JP Perdew, RG Parr, M Levy, and JL Balduz, Jr, Phys Rev Lett 49, 1691 (1982).
[5] R Colle and O Salvetti, Theoret Chim Acta (Berl) 37, 329 (1975).
[6] C Lee, W Yang, and RG Parr, Phys Rev B 37, 785 (1988).
[7] X-Y Pan, V Sahni, and L Massa, Phys Rev Lett 93, 130401 (2004).
[8] Q Wu and T van Voorhis, Phys Rev A 72, 024502 (2005); J Behler, B Delley, K Reuter, and M Scheffler, Phys Rev B 75, 115409 (2007).