Submillimeter-Wave Rotational Spectra of SO Isotopomers in the Electronic States a1Delta and b1Sigma+.

Pure rotational transitions of the sulfur monoxide isotopomers 32S16O, 34S16O, and 32S18O were measured in different vibrational states of the electronic states a1Delta and b1Sigma+ with the Cologne terahertz spectrometer in the submillimeter-wave region between 300 and 1070 GHz. The new lines were analyzed together with previous results from the literature in a global fit yielding isotopically invariant rotational parameters for both states. The measurements reported here allowed for the first time the determination of the parameters U01S and U01O to correct for the breakdown of the Born-Oppenheimer approximation analogously to the X3Sigma- state. Precise equilibrium bond lengths re are given for all states concerned. Copyright 1997 Academic Press. Copyright 1997Academic Press