title: Electronic transitions of ruthenium monoxide.
abstract: The electronic transition spectrum of ruthenium monoxide (RuO) molecule in the spectral region between 545 nm to 640 nm has been recorded and analyzed using laser ablation/reaction free-jet expansion and laser induced fluorescence spectroscopy. The RuO molecule was produced by reacting laser-ablated ruthenium atoms with N2O seeded in argon. Nine vibrational bands were recorded, and they are identified to belong to four electronic transition systems, namely, the [18.1]Ω = 4-X(5)Δ4, [16.0]Ω = 5-X(5)Δ4, [18.1]Ω = 3-X(5)Δ3, and [15.8]Ω = 4-X(5)Δ3 systems. RuO was determined to have a X(5)Δ4 ground state. A least-squares fit of the measured rotational lines yielded molecular constants for the ground and the low-lying electronic states. A molecular orbital energy level diagram has been used to help with the assignment of the observed electronic states.
authors.affiliation: Department of Chemistry, The University of Hong Kong , Pokfulam Road, Hong Kong.
authors.forename: Na
authors.initials: N
authors.lastname: Wang
authors.forename: Y W
authors.initials: YW
authors.lastname: Ng
authors.forename: A S-C
authors.initials: AS
authors.lastname: Cheung