Knowledge Bank

A fourier transform interferometer was used to record the slit jet cooled overtone absorption $spectruma$ of $\mathrm{<mrow\; data-mjx-texclass="ORD">12</mrow>}C2H4$ between 3900 and $7900cm-1$ at a spectral resolution of $0.02cm1$ and a rotational temperature of 53K. In this high frequency range. We perform the analysis of 17 combination bands. For some of them located at 4206, 4322, 4328, 4515, 4730, 5995, and $6150cm-1$ the analysis was complicated by the existence of A-type B-type and C-type Coriolis-type resonances with dark states. For each analysed spectral region, a preliminary calculation of the energy levels was performed taking into account the observed resonances.