Analysis of the D′2g-A′2u transition in the molecular iodine by laser-induced-fluorescence Fourier-transform spectrometry Original Research Article

High resolution spectra of the D′2g → A′2u transition have been recorded in the 30000 cm−1 region using a BOMEM DA3 Fourier Transform spectrometer. From a fit of around 2000 lines measured in 286 bands covering a wide range of v′ and v″ we have derived spectroscopic parameters for the A′2u state and its potential energy curve. The main parameters are: Te (A′2u, v″ = − 12) = 10042.04 (20) cm−1, De (A′2u) = 2505.43 (22) (42) cm−1 and Re (A′2u) = 3.073 Å. The last bound level is either u = 68 or v = 69, and the near-dissociation behaviour has been studied from the higher outer turning points of the RKR curve using the long-range theory of Le Roy.