Knowledge Bank

The region 2000-3600 $cm-1$ in the spectrum of the parent isotopic species of HCNO has been measured with the Bruker IFS 120 HR at Doppler resolution. In addition to the fundamental bands in this region, the spectrum shows a large number of hot bands and combination and difference bands involving the bending modes $\nu 4$ and $\nu 5$ only a few of which were observed in earlier $work\ast$. The line positions have been analyzed, giving information on the bending manifolds in the excited stretching states, which in turn extend our understanding of the interaction between the stretching and bending modes. The interpretation of the line position data is consistent with the intensities observed for the combination and difference bands. With the precision of the spectra we have now obtained, it can be seen that nearly every band identified in this region is at least slightly perturbed. The most important perturbations will be discussed.