Millimetre- and submillimetre-wave spectroscopy of C-13 and N-15 isotopomers of cyanoacetylene, HCCCN, in the ground and vibrationally excited states

The pure rotational spectra of the astrophysically important monosubstitute d HC3N-isotopomers (HCCCN)-C-13, (HCCCN)-C-13, (HCCCN)-C-13 and (HCCCN)-N-1 5 in their ground and various vibrationally excited states, which will be d enoted (v(4), v(5), v(6), v(7)) hereafter, have been studied extensively in the 2 mm region. Transitions of the ground vibrational states and vibratio nal satellites appendant to the two lowest bending fundamentals v(6) and v( 7) have been measured up to 625 GHz. The Fermi resonance system (0,1,0,0)/( 0,0,0,3) has been analyzed for the (HCCCN)-C-13 and (HCCCN)-C-13 isotopomer s for the first time. Furthermore, pure rotational transitions of the four doubly substituted isotopomers (HCCCN)-C-13-C-13, (HCCCN)-C-13-C-13, (HCCCN )-C-13-C-13 and (HCCCN)-C-13-N-15 could be detected for the first time, not only in the ground but also in vibrationally excited states. This work is to provide accurate the astronomical community.