Microwave spectrum of N-methylformamide

Rotational spectra of the N-methylformamide HCONHCH 3 molecule were recorded in the frequency range between 45 and 630 GHz. Analysis was carried out for the trans conformer of the molecule using the Rho axis method where the quadrupole hyperfine structure was taken into account in the first order of perturbation treatment. The analysed dataset for trans conformer contains 18914 A and E transitions with J ≤ 62 in the ground, first, and second excited torsional states. A fit within experimental error is achieved with weighted root-mean-square deviation of 0.85.