Microwave spectroscopic detection of transition metal hydroxides: CuOH andAgOH

Pure rotational spectra of transition metal hydroxides have been reported. Millimeter wave spectra of CuOH and AgOH were recorded in a direct current discharge absorption cell in the range of 200-390 GHz. The spectra of both molecules correspond to that of a near prolate asymmetric top and only a-ty pe R branch transitions were observed. The rotational and centrifugal disto rtion constants of CuOH and AgOH were precisely determined. Centrifugal dis tortion terms up to (NNz10)-N-2 were required to fit the observed line freq uencies of (CuOH)-Cu-63. A preliminary analysis showed that AgOH is also st rongly bent like CuOH with a bond angle smaller by about 2 degrees. (C) 199 9 American Institute of Physics. [S0021-9606(99)01923-6].