LASER-INDUCED FLUORESCENCE OF BACL - THE B2-SIGMA-X2-SIGMA+ ELECTRONIC SYSTEM()

The 799.3 nm Kr+-ion laser radiation and several lines of a monomode t itanium: sapphire laser (767 to 846 nm) have been used to excite the n ear-infrared B2SIGMA+ --> X2SIGMA+ fluorescence of the BaCl molecule. Spectra have been recorded using a high-resolution Fourier transform s pectrometer. Molecular constants are derived for the B2SIGMA+ state le vels ranging from 0 to 15 and for the ground electronic state from 0 t o 20. The observation of Q-type lines in this 2SIGMA-2SIGMA transition shows that there is a substantial PI mixing of the B2SIGMA+ electroni c state.