Rotational spectroscopy of 1-pyrroline: A theoretical study

The 100 m Green Bank Telescope detected ketenimine (CH\(_2\)CNH) in absorption towards the star-forming region Sagittarius B2(N) by means of three rotational transitions: 7\(_{16}\)–8\(_{08}\) at 41.5 GHz, 8\(_{19}\)–9\(_{09}\) at 23.2 GHz and 9\(_{18}\)–10\(_{0,10}\) at 4.9 GHz. This information was recently brought to light by Atacama Large Millimeter/submillimeter Array (ALMA). Below 50 GHz, the rotational spectrum of ketenimine is sparse. In this context, we present the 1-pyrroline rotational spectra for the same frequency range. For spectroscopic parameter calculations, we used quantum chemistry. The PGOPHER program has been used to replicate the species’ pure rotational spectrum. This molecule’s rotating spectrum makes it a viable candidate for upcoming astronomical detections because the radio lines can be estimated with a high degree of precision in mm/sub-mm wave region.