Studies on the Q-branch spectral lines of high-lying rovibrational transitions of diatomic system

An analytical formula is suggested to predict the accurate Q-branch spectral lines of rovibrational transitions for diatomic systems by taking multiple spectral differences, and is applied to study the high-lying Q  -branch emission spectra of the (0, 0) band of the Γ5/24−Φ3/24 and Γ7/24−Φ5/24 systems of TiF molecule using fifteen known accurate experimental transition data. The results show that not only the known experimental transition lines are accurately reproduced, but also the correct values of the unknown spectral lines are predicted.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► We propose a formula to predict Q-branch rovibrational transition spectral lines. ► The formula can reproduce all known experimental rovibrational transition lines. ► The formula can predicts the transition spectral lines missed in experiments.