MILLIMETER WAVE ABSORPTION AND FAR INFRARED LASER MAGNETIC RESONANCE SPECTROSCOPY OF $FO_{2}$*

We have recorded many absorptions due to the $FO_{2}$ radical at frequencies between 130 and 270 GHz. The spectra are all weak, however we have assigned them to fine and hyperfine split components of a-dipole transitions between levels with $6<N<15$ and $0<K<7$. Analysis proved difficult because, in this species, the fine and hyperfine splittings are of the same order of magnitude for many levels. The millimeter wave data were fit together with a set of combination differences extracted from the infrared spectrum of the radical1 in order to determine the molecular parameters. The main uncertainty remaining lies in the K-dependent rotational parameters since no b dipole transitions have yet been assigned. We hope that predictions based on the current parameters will allow their detection by FIR LMR and progress will be reported at this meeting.