THE DETECTION OF LINES IN THE MICROWAVE-SPECTRUM OF INDIUM HYDROXIDE,INOH, AND ITS ISOTOPOMERS

The rotational transition 1(01)-0(00) for InOH in its ground (1)A' sta te has been detected with a pulsed microwave spectrometer; the molecul e was generated by laser ablation of indium(III) hydroxide, In(OH)(3). The same transition has also been recorded for two of its isotopomers , (InOH)-O-18 and InOD. Hyperfine structure arising from both the In-1 15 and H-1 (or D-2) nuclei was observed. The results have been combine d with others from UV spectroscopy to determine an r(0) structure for the molecule: r(0)(In-O) = 0.20167(4) nm, r(0)(O-H) = 0.0911(4) nm, an gle InOH = 132.0(3)degrees. These values reflect the very marked effec t of averaging over a large amplitude bending vibration in InOH in its zero point level. Values for the In-115 and D-2 electric quadrupole c oupling constants and for some smaller, magnetic hyperfine terms are a lso derived. (C) 1997 Academic Press.