The Ultraviolet Spectrum of the FeF Radical: A Study of the ⁶Π–X⁶Δ and ⁶Φ–X⁶Δ Band Systems at 330 and 323 nm Respectively

Abstract

Two band systems of FeF have been recorded at Doppler-limited linewidths by laser-induced fluorescence. The 330-nm system provided data for three subbands of the (0,0) band of the ⁶Π–X⁶Δ system and showed that levels of the ⁶Π_5/2 and ⁶Π_3/2 components are significantly perturbed. In the 323-nm system, the (0,0) band of the ⁶Φ–X⁶Δ system was found to be overlapped by the (1,0) band of the ⁶Π–X⁶Δ system. Data were obtained for three subbands of the (1,0) ⁶Π–X⁶Δ system and for five subbands of the (0, 0) ⁶Φ–X⁶Δ system. This work considerably extends the previous study by Pouilly et al. (B. Pouilly, J. Schamps, D. J. W. Lumley, and R. F. Barrow, J. Phys. B11, 2281–2287 (1978)) because it is a higher resolution study with a lower temperature production of FeF by a continuous flow discharge method. The data recorded were combined with millimeter-wave data for FeF in the X⁶Δ state and fitted with an effective Hamiltonian to determine the major parameters for FeF in the X⁶Δ, ⁶Π, and ⁶Φ electronic levels.