Knowledge Bank

A new analysis of the $\nu 3,\nu 6$, and $\nu 4$ interacting bands of $D_{2} $CO has been carried out in the $8-12m$ region using high resolution Fourier transform spectra recorded at Giessen. As compared to the previous study of these $bands,h$ improvements were obtained in the present analysis. In order to get the upper state parameters (band centres, rotational and coupling constants), the resulting $\nu 3,\nu 6$, and $\nu 4$ experimental energy levels were introduced in a least squares fit calculation together with the microwave measurements available in the literature. In this calculation, which allowed to reproduce both the infrared and microwave measurements within their experimental accuracies, the A-B- and C- Coriolis type interactions involving $\nu 4$ and $\nu 6,\nu 3$ and $\nu 4$ and $\nu 3$ and $\nu 6$ respectively were explicitly taken into account.