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arXiv · 2506.19116

Rovibrational computations for the He$_2$ a $^3\Sigma_\mathrm{u}^+$ state including non-adiabatic, relativistic, and QED corrections

Ádám Margócsy·Balázs Rácsai·Péter Jeszenszki·Edit Mátyus
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Abstract

A potential energy curve (PEC) accurate to a fraction of 1 ppm ($1:10^6$) is computed for the $^3\Sigma_\mathrm{u}^+$ state of He$_2$ endowed with relativistic and QED corrections. The nuclear Schr\"odinger equation is solved on this PEC with diagonal Born-Oppenheimer and non-adiabatic mass corrections to obtain highly accurate rotational-vibrational levels. The computed rovibrational intervals and fine-structure splittings, spanning over several orders of magnitude in energy, are found to be in remarkable agreement with available high-resolution spectroscopy data.

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Ádám Margócsy, Balázs Rácsai, Péter Jeszenszki, Edit Mátyus. 2025-06-23. Rovibrational computations for the He$_2$ a $^3\Sigma_\mathrm{u}^+$ state including non-adiabatic, relativistic, and QED corrections. https://doi.org/10.1021/acs.jctc.5c01855

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