arXiv 0905.16712009-05physics.atom-ph

Must Kohn-Sham Oscillator Strengths be Accurate at Threshold?

Zeng-hui Yang, Meta van Faassen, Kieron Burke

备注：: 7 pages, 7 figures, submitted to J. Chem. Phys
DOI：: 10.1063/1.3222638

英文摘要：

The exact ground-state Kohn-Sham(KS) potential for the helium atom is known from accurate wavefunction 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.

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