title: Note: Observation of a new electronically excited state of cobalt monoxide.
abstract: The laser-induced fluorescence excitation spectra of jet-cooled CoO molecules have been recorded in the energy region of 21,800-25,000 cm(-1). Apart from the seven vibronic bands assigned to the known G(4)Φ(9∕2)(υ(')) - X(4)Δ(7∕2)(υ(") = 0) progression [M. Barnes, D. J. Clouthier, P. G. Hajigeorgiou, G. Huang, C. T. Kingston, A. J. Merer, G. F. Metha, J. R. D. Peers, and S. J. Rixon, J. Mol. Spectrosc. 186, 374 (1997)], we observed a new band system assignable to the [22.95](4)Δ(7∕2)(υ(') = 0 - 4) - X(4)Δ(7∕2)(υ(") = 0) progression. Extensive perturbations among these vibronic bands have been revealed by means of reduced energy plots. The new electronically excited (4)Δ state has been determined to be most likely of an electronic configuration (2pπ)(3)(4sσ)(2)(3dδ)(3)(3dπ)(3) based on the charge-transferred promotion model.
authors.forename: Jianzheng
authors.initials: J
authors.lastname: Zang
authors.forename: Qun
authors.initials: Q
authors.lastname: Zhang
authors.forename: Chengbing
authors.initials: C
authors.lastname: Qin
authors.forename: Zhong
authors.initials: Z
authors.lastname: Gu
authors.forename: Xilin
authors.initials: X
authors.lastname: Bai
authors.forename: Yang
authors.initials: Y
authors.lastname: Chen