Extracting molecular potentials from incomplete spectroscopic information

Abstract

We extend our recently developed inversion method to extract excited-state potentials from fluorescence line positions and line strengths. We consider a previous limitation of the method arising due to insufficient input data in cases where the relatively weaker emission data are not experimentally available. We develop a solution to this problem by ‘regenerating’ these weak transition lines via applying a model potential, e.g. a Morse potential. The result of this procedure, illustrated for the Q-branch emission from the lowest three vibrational levels of the B(¹Π) state of LiRb, is shown to have an error of 0.29 cm⁻¹ in the classically allowed region and a global error of 5.67 cm⁻¹ for V ≤ E(ν′ = 10). The robustness of this procedure is also demonstrated by considering the statistical error in the measured line intensities.

Keywords:

• molecular potential
• spectroscopy
• inversion method
• fluorescence line positions
• fluorescence strengths
• insufficient input