Rotational analysis of the BaI C2 - X2+ band system for the Dv=0 progression (v=0-12)
Leach, C.A.; Tsekouras, A.A.; Zare, R.N.; Dept. of Chem., Stanford Univ., CA, USA
Journal of Molecular Spectroscopy, vol.153, no.1-2, p. 59-72, May-June 1992 23 Refs.
High-resolution spectra of the P12-, R1-, P2-, and R21-branch members of the BaI C2 - X2+ (v,v) bands with v=0, 1, 4, 8, and 12 have been recorded using selectively detected laser-induced fluorescence (SDLIF). In addition, transitions involving high J" levels have been observed by undispersed fluorescence in the P12 and P2 branches of the (0,0), (1,1), (2,2), and (3,3) bands, and near the bandheads in the P1, Q12, P21, and Q2 branches of the (0,0) band. These data are combined with earlier optical measurements of the same electronic band system by Johnson et al. (1981, 1985) and Zhao et al. (1991) and Zhao et al. (1991) and with microwave measurements of low J" levels for v=0-5 of the X2+ state by Torring and Dobl. Spectroscopic constants are obtained for the C2 and X2+ states using a weighted nonlinear least-squares fit to the optical and microwave transition wavenumbers, and bandhead positions for v<=12. The present set of 31 constants reproduces the positions of 5032 optical transitions with a standard deviation of 2.4x10-3 cm-1. No frequency perturbations are observed in the authors' data.