The BaI X2Sigma+ and B2Sigma+ Electronic States Through B2Sigma+-X2Sigma+ and C2Pi-X2Sigma+ Band Systems Analysis.

The near-infrared spectrum of the B2Sigma+-X2Sigma+ band system of the BaI molecule, obtained from the chemiluminescent reaction Ba + I2 and also by laser-induced fluorescence (LIF), was recorded by using Fourier transform spectroscopy (FTS). The LIF spectra were obtained by using a Ti:sapphire single-mode laser excitation. Resolved rotational data, originating from 32 vibrational levels (0 </= v </= 31) in the X2Sigma+ state and from 24 vibrational levels (0 </= v </= 19, and v = 21, 22, 23, 26) in the B2Sigma+ state, were used in the final analysis. Previously recorded data for the C2Pi-X2Sigma+ band system (with Deltav = 0), taken from C. A. Leach, A. A. Tsekouras, and R. N. Zare, J. Mol. Spectrosc. 153, 59-72 (1992), were added to the present work data field. Accurate and improved molecular constants for the X2Sigma+, B2Sigma+, and C2Pi states were derived from a simultaneous treatment of the whole data set. Copyright 1999 Academic Press.