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arXiv · 1810.11288

Nonrelativistic energy levels of helium atom

D. T. Aznabaev·A. K. Bekbaev·Vladimir I. Korobov
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Abstract

The nonrelativistic ionization energy levels of a helium atom are calculated for $S$, $P$, $D$ and $F$ states. The calculations are based on the variational method of "exponential" expansion. The convergence of the calculated energy levels is studied as a function of the number of basis functions $N$. This allows us to claim that the obtained energy values (including the values for the states with a nonzero angular momentum) are accurate up to 28-35 significant digits. Calculations of the nonrelativistic ionization energy of the negative hydrogen ion H$^-$ are also presented.

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D. T. Aznabaev, A. K. Bekbaev, Vladimir I. Korobov. 2018-10-26. Nonrelativistic energy levels of helium atom. https://doi.org/10.1103/physreva.98.012510

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