Study of adiabatic connection in ground - state density functional theory

Submitted for the MAR16 Meeting of The American Physical Society Study of adiabatic connection in ground-state density functional theory MANOJ HARBOLA, RABEET CHAUHAN, Indian Inst of Tech-Kanpur, RABEET S. CHAUHAN COLLABORATION — By employing modified [1] variational form of Le-Sech wavefunctions [2] for two-electron systems, accurate wavefunctions for He-like atoms corresponding to their ground-state density are obtained for varying strength, given by a parameter α (0 ≤ α ≤1), of electron-electron interaction. Using these, it is shown explicitly that (i) the total energy varies almost linearly as a function of α, and (ii) the ionization potential remains unchanged [3] as α is varied. Furthermore, kinetic energy contribution to the density-functional exchange-correlation energy is calculated using the adiabatic connection formula [4] and shown to match that calculated on the basis of Kohn-Sham calculation. Finally, the exchange-correlation energy obtained for different values of α is employed to analyze several hybrid exchange-correlation energy functionals in use. [1] R.S. Chauhan and M.K. Harbola, Chem. Phys. Lett. 639C, 248(2015) [2] C. Le Sech, J. Phys. B: Atom. Mol. Opt. Phys. 30, L47(1997) [3] M. Levy, J. P. Perdew and V. Sahni, Phys. Rev. A 30, 2745(1984) [4] R. Harris and R.O. Jones, J. Phys. F: Met. Phys. 4 1170 (1974); D.C. Langreth and J.P. Perdew, Phys. Rev. B 15, 2884 (1977) Manoj Harbola Indian Inst of Tech-Kanpur Date submitted: 03 Nov 2015 Electronic form version 1.4