The pure rotational spectrum of the FeF radical in its 6Δi ground electronic state has been recorded using millimeter/submillimeter direct absorption techniques. Transitions arising from all six spin orbit components have been observed in the v=0, 1. and 2 vibiational levels of 56FeF, the main isotopic species, and also in the less abundant 54Fe isotopomer. Hyperfine splittings, arising from the 19F nuclear spin of I=1/2, were resolved in the majority of transitions recorded, and lambda-doubling interactions were observed in the Ω=3/2. 1/2. and -1/2 spin-orbit ladders. The complete data set has been analyzed using a 6Δ Hamiltonian, and rotational, spin-orbit, spin-spin lambda-doubling, and hyperfine constants determined. This study has conclusively demonstrated that the ground electronic state of FeF is 6Δi. It also suggests that FeF has more covalent character to its bonding than alkaline earth or alkali metal counterparts.
ASJC Scopus subject areas
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry