ExoMol line lists – LVI. The SO line list, MARVEL analysis of experimental transition data and refinement of the spectroscopic model

Abstract

A semi-empirical IR/Vis line list, SOLIS, for the sulphur monoxide molecule 32S16O is presented. SOLIS includes accurate empirical rovibrational energy levels, uncertainties, lifetimes, quantum number assignments, and transition probabilities in the form of Einstein A coefficients covering the X 3Σ−, a 1Δ, b 1Σ+, A 3Π, B 3Σ−, A″ 3Σ+, A′ 3Δ and e 1Π systems and wavenumber range up to 43303.5 cm−1 (≥230.93 nm) with J ≤ 69. SOLIS has been computed by solving the rovibronic Schrödinger equation for diatomics using the general purpose variational code Duo and starting from a published ab initio spectroscopic model of SO (including potential energy curves, coupling curves, (transition) dipole moment curves) which is refined to experimental data. To this end, a database of 50 106 experimental transitions, 48 972 being non-redundant, has been compiled through the analysis of 29 experimental sources, and a self-consistent network of 8558 rovibronic energy levels for the X, a, b, A, B, and C electronic states has been generated with the marvel algorithm covering rotational and vibrational quantum numbers J ≤ 69 and v ≤ 30 and energies up to 52350.40 cm−1. No observed transitions connect to the B 3Σ−(v = 0) state which is required to model perturbations correctly, so we leave fitting the B 3Σ− and C 3Π state UV model to a future project. The SO line list is available at ExoMol from www.exomol.com.

Full spectroscopic model and trihybrid experimental-perturbative-variational line list for CN

“…Additionally, all spin-orbit (ASO), spin-spin (λSS), spinrotation (γSR), Λ-doubling (λopq, λp2q and λq), angular momentum (L+) and Born-Oppenheimer breakdown (BOrot) interactions relevant to the X 3 Σ − , a 1 ∆ and A 3 Π electronic states were considered in this energy spectroscopic model. Specifically, the Born-Oppenheimer breakdown correction allows for a position-dependent variation of the rotational mass (Le Roy & Huang 2002;Brady et al 2023), which is treated here for 14 N 1 H only. This has shown to be Table 1.…”