Theoretical investigation on spectroscopic characteristics of 14 Λ-S and 27 Ω states of OH+ cations

Based on theoretical frameworks such as icMRCI+Q and the accurate treatment of scalar relativistic effect, core-valence electron correlation, complete basis set limit, and spin-orbit coupling effect, this article calculates the relevant spectroscopic and vibrational-rotational transition data for 14 Λ-S and 27 Ω states of OH+ cation. The dataset includes potential energy curves of 14 Λ-S and 27 Ω states, 7 pairs of transition dipole moments between the 6 Ω states [X3Σ-0+, X3Σ-1, (1)2, (2)2, (2)1, (1)0-], and distributions of the radiative lifetime varying as the J' of the (2)21st well(υ' = 0 − 2, +), (2)1(υ' = 0−9, +), and (1)0-(υ' = 0−8, +) states.

Based on the potential energy curves and transition dipole moments mentioned above, by solving the vibrational-rotational Schrödinger equation for nuclear motion and the formulas (1-4) in the article, we obtained the spectroscopic constants (Te, Re, ωe, ωexe, Be, αe, D0, and De) and molecular constants for 12 Λ-S and 27 Ω bound and weakly bound states, the vibrational-rotational transition data for the seven pairs of transitions between X3Σ-0+, X3Σ-1, (1)2(υ' = 0–6), (2)21st well(υ' = 0–2), (2)1(υ' = 0–9), and (1)0-(υ' = 0–8) states with less perturbation by other Ω states, such as the transition wave numbers, Einstein A coefficients, vibrational branching ratios, weighted absorption oscillator strengths, wavelengths, radiation lifetimes and radiation widths of four excited Ω states[(1)2(υ' = 0−6, J' = 2, +), (2)21st well(υ' = 0−2, J' = 2, +), (2)1(υ' = 0−9, J' = 1, +), and (1)0-(υ' = 0−8, J' = 0, +)].