Knowledge Bank

The absorption spectrum of deutereted cyanoacethylene between 180 and $370 cm^{-1}$ has been recorded in W\"{u}ppertal with a resolution of $0.02 cm^{-1}$.The following transitions and their associated hot bands have been observed: $v_{7} \leftarrow G.S, v^{1}_{5}\leftarrow v^{1}_{7}.v^{1}_{6}\leftarrow v^{1}_{7}$ and $v_{4} \leftarrow v^{1}_{6}$. From these spectra we have obtained with an accuracy in the range of $0.01 cm^{-1}$ the vibrational energies of most states of DCCCN below $1100 cm^{-1}$. These results combined with the Stark transitions $\Delta v_{5} =2^{(1)}$ and the microwave $analysis^{[2]}$ yields the determination of any $x_{ij}$ and $g_{ij}$ anharmonicity parameters with $ij = 4$ to 7. The observation of the crossing of $v_{4}$ with $4v^{2}_{7}$ at $J=47$ and with $4v^{0}_{7}$ at $J = 57$ confirms the anharmonic interactions scheme of Plummer $et al.^{[2]}$