Must Kohn-Sham oscillator strengths be accurate at threshold?
The exact ground-state Kohn-Sham (KS) potential for the helium atom is known from accurate wave function calculations of the ground-state density. The threshold for photoabsorption from this potential matches the physical system exactly. By carefully studying its absorption spectrum, we show the answer to the title question is no. To address this problem in detail, we generate a highly accurate simple fit of a two-electron spectrum near the threshold, and apply the method to both the experimental spectrum and that of the exact ground-state Kohn-Sham potential.
- Department of Chemistry, University of California, Irvine, California 92697 (United States)
- Department of Theoretical Chemistry, Faculty of Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1083, NL-1081 HV Amsterdam (Netherlands)
- Publication Date:
- OSTI Identifier:
- Resource Type:
- Journal Article
- Resource Relation:
- Journal Name: Journal of Chemical Physics; Journal Volume: 131; Journal Issue: 11; Other Information: DOI: 10.1063/1.3222638; (c) 2009 American Institute of Physics
- Country of Publication:
- United States
- 74 ATOMIC AND MOLECULAR PHYSICS; 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ABSORPTION SPECTRA; ATOMS; ELECTRON SPECTRA; GROUND STATES; HELIUM; OSCILLATOR STRENGTHS; PHOTON-ATOM COLLISIONS; POTENTIALS; WAVE FUNCTIONS ATOM COLLISIONS; COLLISIONS; ELEMENTS; ENERGY LEVELS; FLUIDS; FUNCTIONS; GASES; NONMETALS; PHOTON COLLISIONS; RARE GASES; SPECTRA