Non-adiabatic, Relativistic, and Leading-order QED Corrections for Rovibrational Intervals of ${}^4$He${}_2^{+}$ ($X{}^2{\Sigma }_{\mathrm{u}}^{+}$)

Abstract

The rovibrational intervals of the ${}^4$He${}_2^{+}$ molecular ion in its $X{}^2{\Sigma }_{\text{u}}^{+}$ ground electronic state are computed by including the non-adiabatic, relativistic, and leading-order quantum-electrodynamics corrections. Good agreement of theory and experiment is observed for the rotational excitation series of the vibrational ground state and the fundamental vibration. The lowest-energy rotational interval is computed to be $70.93769(10)$ cm${}^{-1}$ in agreement with the most recently reported experimental value, $70.937589(23)(60{)}_{\text{sys}}$ cm${}^{-1}$ [L. Semeria, P. Jansen, G.-M. Camenisch, F. Mellini, H. Schmutz, and F. Merkt, Phys. Rev. Lett. 124, 213001 (2020)].

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Cited by in corpus (2)

• Variational versus perturbative relativistic energies for small and light atomic and molecular systems
• QED theory of the nuclear magnetic shielding in H and ${}^3$He