High-Resolution Fourier Transform Spectroscopy of Three Near-Infrared Transitions of NiF

The emission spectrum of the NiF radical has been recorded by high-resolution Fourier transform spectroscopy in the region 6000-12 000 cm⁻¹. Numerous new near-infrared bands were observed. In this paper three electronic transitions are analyzed leading to the identification of two new electronic states: a 12.0]²Φ_7/2 state and a 11.1]²Π_3/2 state located, respectively, at 12 008.89 and 11 096.05 cm⁻¹ above the X²Π_3/2 ground state. These electronic states can be correlated to the 3d⁸(³F)4s]²F atomic term of Ni⁺ as predicted by Carette et al. J. Mol. Spectrosc.161, 323-335 (1993)].