SPECTROCOPY AND PHOTOPHYSICS OF REFRACTORY MOLECULES AT LOW TEMPERATURE. THE GREEN SYSTEMS OF ZrS

Author Institution: Laser Chemistry Group, Division of Chemistry, National Research Council of CanadaThe diatomic molecule ZrS has been observed by laser induced fluorescence in a supersonic molecular beam following reaction of laser-vaporised zirconium atoms with = 2\% carbonyl sulfide (OCS) added into a flow of He carrier gas. Two band systems have been observed in the 413-700 nm region. The R-heads of their band origins lie at 20218.9 and $20208.3 cm^{-1}$. The former is tentatively ascribed to the $E^{1}\Sigma^{+}X^{3}\Sigma^{+}$ transition; the latter remains unassigned but is shown to borrow all of its intensity from the former through a simple intensity borrowing mechanism. A vibrational analysis leads to the following molecular constants for the ground state: we $548.4 cm^{-1}, w_{e}x_{e} = 1.6 cm^{-1}$. Frank-Condon factors for several vibronic transitions are also reported. Intrinsic radiative lifetimes of several vibrational levels of both upper states have been measured, and confirm that the two states perturb each other. A limited deperturbation analysis has been carried out. Vibrational constants, mixing coefficients, interaction matrix elements and other spectroscopic parameters are reported