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arXiv · 2208.07895

HCl, DCl and TCl diatomic molecules in their ground state: predicting Born-Oppenheimer rovibrational spectra

Horacio Olivares-Pilón·Alexander V. Turbiner
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Abstract

The analytic Born-Oppenheimer (B-O) potential curve for the ground state $X^1Σ^+$ of the molecule (H,D,T)Cl is constructed for the whole range of internuclear distances $R \in [0,\infty)$ with an accuracy of 3-5 figures in comparison with the RKR-style potential curve derived from available experimental data on vibrational energies. With an accuracy of 3-4 significant figures in the energies, it is predicted for HCl (DCl, TCl) the 836 (1625, 2366) B-O rovibrational bound states with maximal vibrational number $ν_{max} = 20\, (29, 35)$ and maximal angular momentum $L_{max} = 64\, (90, 109)$ including 24 (46, 63) weakly-bound states (close to the dissociation limit) with energies $\lesssim 10^{-4}$ Hartree. Insufficiency of existing experimental data is indicated and a prediction of the bulk of missing rovibrational states is made for all HCl, DCl, TCl molecules.

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Horacio Olivares-Pilón, Alexander V. Turbiner. 2023-06-25. HCl, DCl and TCl diatomic molecules in their ground state: predicting Born-Oppenheimer rovibrational spectra. https://doi.org/10.1088/1361-6455%2Face176

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