15min:

SARAH E. FREY AND TIMOTHY C. STEIMLE, Department of Chemistry and Biochemistry, Arizona State University, Tempe,AZ 85287, USA.

Transitions of the A² - X^{2 +} band system of barium monohydroxide, BaOH, were observed and recorded from 11483-11485 cm^-1 and 12041-12044 cm^-1. The features were readily identified using the results of the Doppler-limited measurements. The laser induced fluorescence (LIF) spectrum was analyzed to give optimized field-free excited state parameters. The parameters for the X^{2 +} state were constrained to the previously determined values. The permanent electric dipole moments for the X^{2 +} and A² states have been determined from the analysis of the optical Stark spectra for the R₂₁(0.5), Q₂₁(1.5), and R₂(0.5) lines. The obtained values were µ(X^{2 +})= 1.426(38)D and µ(A² )= 0.477(7) D. The results are compared with predicted values from semi-empirical models and those for CaOH and SrOH.