Knowledge Bank

The infrared spectrum of gas phase methyl nitrite $(CH3ONO)$ has been recorded at high resolution between 600 and $4000cm-1$. The conformational doublets due to the cis and trans conformers are clearly separated in a number of the fundamentals. Previous work in the microwave has established that the barrier to rotation of the methyl group in the trans form is very $lowa$ and the infrared bands observed in this study are very congested. The barrier in the cis conformer is much $higherb$. The $\nu 8$ at $841cm-1$ was assigned by previous workers to the N-O stretch of the cis $conformerc$ and is partially overlapped by the $\nu 8$ of the trans conformer. In this study, spectra taken at $0.0015cm-1$ resolution on the PNNL IFS120/HR in a 20 cm cell were used to assign more than 800 A-type rovibrational lines of the cis $\nu 8$ between 815 and $865cm-1$.