MOLECULAR BEAM LASER SPECTROSCOPY OF THE YTTRIUM MONOSULFIDE MOLECULE

Author Institution: Laser Chemistry group, Steacie Institute for Molecular Sciences, National Research Council of CanadaThe electronic spectroscopy of the yttrium monosulfide molecule (YS) has been studied in the pulsed supersonic jet apparatus. The molecules were produced by chemical reaction in a laser-generated plasma. Laser induced fluorescence spectra were recorded in the region 600-800 mm using a pulsed dye laser ($0.006 cm^{-1}$ bandwidth). In addition to the previously reported $A^{2}\Pi-X^{2}\Sigma^{+}$ and $B^{2}\Sigma^{+}-X^{2}\Sigma^{+}$ systems, some new transitions were observed. Several bands were probed at a resolution of 120 MHz using a single mode ring dye laser to excite flourescence. Perturbations in the $B^{2}\Sigma^{+}- X^{2}\Sigma^{+}$ (0,0) band were observed and will be discussed. Stark spectroscopy was performed on the first lines of the $P_{c}$ and $R_{e}$ branches of the $B^{2}\Sigma^{+}- X^{2}\Sigma^{-}$ (0,0) band in order to determine the dipole moments of the X and B states respectively. Results are compared with recent work on related group III transition metal molecules