Must Kohn-Sham oscillator strengths be accurate at threshold?

Journal Article · Mon Sep 21 00:00:00 EDT 2009 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.3222638· OSTI ID:21559772

Zenghui, Yang; Burke, Kieron ^[1]; Faassen, Meta van ^[2]

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1. Department of Chemistry, University of California, Irvine, California 92697 (United States)
2. Department of Theoretical Chemistry, Faculty of Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1083, NL-1081 HV Amsterdam (Netherlands)

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.

• OSTI ID: 21559772
• Journal Information: Journal of Chemical Physics, Vol. 131, Issue 11; Other Information: DOI: 10.1063/1.3222638; (c) 2009 American Institute of Physics; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

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