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arXiv · 2506.19120

Rovibrational computations for He$_2^+$ X $\Sigma_\mathrm{u}^+$ including non-adiabatic, relativistic and QED corrections

Edit Mátyus·Ádám Margócsy
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Abstract

We report the potential energy curve, the diagonal Born-Oppenheimer, non-adiabatic mass, relativistic, and leading-order QED corrections for the ground electronic state of the helium dimer cation; the higher-order QED and finite-nuclear size effects are also estimated. The computations are carried out with an improved error control and over a much broader configuration range compared to earlier work [D. Ferenc, V. I. Korobov, and E. M\'atyus, Phys. Rev. Lett. 125, 213001 (2020)]. As a result, all rovibrational bound states are reported with an estimated accuracy of 0.005 cm$^{-1}$.

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Edit Mátyus, Ádám Margócsy. 2025-06-23. Rovibrational computations for He$_2^+$ X $\Sigma_\mathrm{u}^+$ including non-adiabatic, relativistic and QED corrections. https://doi.org/10.1080/00268976.2025.2611409

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