Fourier transform spectroscopy of the 1 3Σ+g–a 3Σ+u transition of the 6Li2 molecule

Abstract

The 1 3Σ+ g –a 3Σ+ u transition of 6Li2 has been observed via collisionally induced fluorescence, excited by visible lines of an argon‐ion laser and detected at high resolution with a Fourier–transform spectrometer in the 8200–10 100 cm− 1 region. By combining the results with previously obtained data on 7Li2 [F. Martin, R. Bacis, J. Vergès, C. Linton, G. Bujin, C. H. Cheng, and E. Stad, Spectrochim. Acta Part A 4 4, 1369 (1988)], an accerate, isotopically consistent description of both states has been obtained for 1≤v’≤7 and 0≤v‘≤7. Equilibrium constants, Rydberg‐Klein‐Rees potential curves, and dissociation energies have been determined and found to be in good agreement with a b i n i t i o calculations. From the analysis, the following positions and dissociation energies of the two states were found. For 1 3Σ+ g , T e (cm− 1) is 16 328.8(1.7) and D e (cm− 1) is 7091.6(1.2). For a 3Σ+ u , T e (cm− 1) is 8183.8(1.5) and D e (cm− 1) is 333(1).