The electronic valence states of CuO: Radiative lifetimes of the A, A′, C, and D states

• Published in: Journal of molecular spectroscopy 1983-10, Vol.101 (2), p.358-368
• Main Authors: Delaval, J.M., David, F., Lefebvre, Y., Bernage, P., Niay, P., Schamps, J.
• Format: Article
• Language: English
• Subjects: Atomic and molecular physics; Exact sciences and technology; Fluorescence and phosphorescence; radiationless transitions, quenching (intersystem crossing, internal conversion); Molecular properties and interactions with photons; Physics
• ISSN: 0022-2852; 1096-083X
• DOI: 10.1016/0022-2852(83)90141-8

Radiative lifetimes of several electronic states of CuO have been determined by recording the exponential decay of the fluorescence following resonant excitation by a pulsed dye laser. The lifetimes extrapolated to zero pressure have been found to be 0.65 μsec for the A 2Σ − state, 1.3 μsec for the C 2Π state, 1.8 μsec for the D 2Δ state, and more than 5 μsec for the A′ ( Ω = 1 2 ) state. In connection with an energy level diagram, these values support the assignment of the A, C, and D states, to the 3 d Cu + 9 4 s Cu + 2 p O − 5 ( σ 2 π 3) structure. The long-lived A′ state could be either another doublet or a contaminated quartet Ω = 1 2 component of the same structure as the three other states or a state of the 3d Cu + 9 σ ∗2 2pπ 4 structure.