Resonant two-photon ionization spectroscopy of jet-cooled RuC

Abstract

A resonant two-photon ionization study of the jet-cooled RuC molecule has identified the ground state as a 1Σ+ state arising from the 10σ211σ25π42δ4 configuration. The 3Δi state arising from the 10σ211σ25π42δ 312σ1 configuration lies very low in energy, with the 3Δ3 and 3Δ2 components lying only 76 and 850 cm-1 above the ground state, respectively. Transitions from the X1Σ+, 3Δ3, and 3Δ2 states to the 3Π2, 3Π1, 33, 34, 13, and 1Π1 states arising from the 10σ211σ25π42δ 36π1 configuration have been observed in the 12700-18100cm-1 range, allowing all of these states to be placed on a common energy scale. The bond length increases as the molecule is electronically excited, from r0=1.608Å in the 2δ4, X1Σ+ state, to 1.635 Å in the 2δ312σ1, 3Δ state, to 1.66 Å in the 2δ36π1, 3Π and 3 states, to 1.667 Å in the 2δ36π1, 1 and 1.678 Å in the 2δ36π1, 1Π state. A related decrease in vibrational frequency with electronic excitation is also observed. Hyperfine splitting is observed in the 2δ312σ1, 3Δ3 state for the 99Ru(I=5/2)12C and 101Ru(I=5/2)12C isotopic combinations. This is analyzed using known atomic hyperfine parameters to show that the 12σ orbital is roughly 83% 5sRu in character, a result in good agreement with previous work on the related RhC and CoC molecules. © 1998 American Institute of Physics.