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

Abstract

The analytic Born-Oppenheimer (B-O) potential curve for the ground state $X^1{\Sigma }^{+}$ 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 ${\nu }_{max}=20(29,35)$ 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.

arXiv comment22 pages, 4 figures, 6 tables, 22 references: the final text, to be published in J Phys B

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