MILLIMETER-WAVE ROTATIONAL SPECTRA OF INDIUM MONOFLUORIDE

The millimeter wave rotational spectra of indium monofluoride (InF) ha ve been studied in the 250-300 GHz frequency region. Three rotational transitions of (InF)-In-115 in the v = 0, 1 and 2 vibrational states a nd two rotational transitions of the less abundant (InF)-In-113 in the v = 0 state with resolved hyperfine structures have been measured. Th e analysis including previous measurements on the lower rotational tra nsitions in the microwave region yielded improved and extended sets of Dunham parameters. The comparison of the results for the two isotopic species of InF indicates a similar deviation from the Born-Oppenheime r approximation as for InCl.