HIGH-RESOLUTION FOURIER-TRANSFORM INFRARED-EMISSION SPECTRA OF BARIUMMONOFLUORIDE

The high-resolution infrared emission spectra of gas-phase barium mono fluoride have been observed by Fourier transform spectrometry. Vibrati on-rotation bands were analyzed for the three most abundant isotopomer s ((BaF)-Ba-138, from 1-0 to 12-11; (BaF)-Ba-137, from 1-0 to 5-4; (Ba F)-Ba-136, from 1-0 to 4-3) of the ground X(2) Sigma(+) state. The Dun ham coefficients, Y-lm, have been derived for all three isotopomers by fitting about 1750 lines for (BaF)-Ba-138, about 270 lines for (BaF)- Ba-137, and about 70 lines for (BaF)-Ba-136 to the traditional Dunham model. In addition, the mass-reduced Dunham constants, U-lm have been calculated from a global least-squares fit. (C) 1995 Academic Press, I nc.