Non-adiabatic mass-correction functions and rovibrational states of $^4$He$_2^+$ ($X\ ^2Σ_\text{u}^+$)

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doi:10.1063/1.5050403

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arXiv · 1810.05584

Non-adiabatic mass-correction functions and rovibrational states of $^4$He$_2^+$ ($X\ ^2Σ_\text{u}^+$)

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Abstract

The mass-correction functions in the second-order non-adiabatic Hamiltonian are computed for the $^4$He$^+_2$ molecular ion using the variational method, floating explicitly correlated Gaussian functions, and a general coordinate-transformation formalism. When non-adiabatic rovibrational energy levels are computed using these (coordinate-dependent) mass-correction functions and a highly accurate potential energy and diagonal Born-Oppenheimer correction curve, significantly improved theoretical results are obtained for the nine rotational and two rovibrational intervals known from high-resolution spectroscopy experiments.

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Edit Mátyus. 2018-10-12. Non-adiabatic mass-correction functions and rovibrational states of $^4$He$_2^+$ ($X\ ^2Σ_\text{u}^+$). https://doi.org/10.1063/1.5050403

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