The Rotational Spectrum of OCCCS Revisited

The rotational spectrum of the linear chain molecule tricarbon oxide sulfide, OCCCS, was recorded at room temperature between 118 and 179 GHz using a new commercial millimeter-wave spectrometer. The observed transitions were analyzed together with hitherto unassigned transitions from measurements between 78 and 118 GHz. About 1900 rotational transitions of OCCCS in the vibrational ground state and in 13 excited bending states could be assigned, the latter including the eighth, ninth, and tenth excited state of the low-lying bending mode nu(7) as well as the second excited state of the bending mode nu(6). Besides the determination of effective constants for these newly identified vibrational states, our data also served to considerably improve the effective constants for some of the bending states already characterized in previous publications. Copyright 2000 Academic Press.