Must Kohn-Sham oscillator strengths be accurate at threshold?
نویسندگان
چکیده
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.
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ورودعنوان ژورنال:
- The Journal of chemical physics
دوره 131 11 شماره
صفحات -
تاریخ انتشار 2009