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arXiv · 1203.3927

Accurate Born-Oppenheimer potential for HeH+

Krzysztof Pachucki
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Abstract

We demonstrate high accuracy calculations for the HeH$^+$ molecule using newly developed analytic formulas for two-center two-electron integrals with exponential functions. The Born-Oppenheimer potential for the ground electronic $^1Σ^+$ state is obtained in the range of 0.1 -- 60 au with precision of about $10^{-12}$ au. As an example at the equilibrium distance $r=1.463\,283$ au the Born-Oppenheimer potential amounts to $-2.978\,708\,310\,771(1)$. Obtained results lay the ground for theoretical predictions in HeH$^+$ with spectroscopic precision.

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Krzysztof Pachucki. 2012-03-18. Accurate Born-Oppenheimer potential for HeH+. https://doi.org/10.1103/physreva.85.042511

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