Transition frequencies of ethanimine (CH_3_CHNH)

In addition, its identification in Titan's atmosphere would be important for understanding the abiotic synthesis of organic species. An accurate computational characterization of the molecular structure, energetics, and spectroscopic properties of the E and Z isomers of ethanimine, CH_3_CHNH, has been carried out by means of a composite scheme based on coupled-cluster techniques, which also account for extrapolation to the complete basis-set limit and core-valence correlation correction, combined with density functional theory for the treatment of vibrational anharmonic effects.

By combining the computational results with new millimeter-wave measurements up to 300GHz, the rotational spectrum of both isomers can be accurately predicted up to 500GHz. Furthermore, our computations allowed us to revise the infrared spectrum of both E- and Z-CH_3_CHNH, thus predicting all fundamental bands with high accuracy.