Quadratic complete basis set ab initio and hybrid density functional theory studies of the stability of HNC, HCN, H2NCH and HNCH2, their isomerizations, and the hydrogen insertion reactions for HCN and HNC

Ab initio and hybrid density functional theory (DFT) studies have been performed in order to generate an energy profile for the transformation of hydrogen cyanide (HCN) into H2CNH, the isomerization, and the hydrogen insertion reaction. In this way, the feasibility of the chemical transformation, as well the stability of some isomers, was discussed. Furthermore, the reliability of hybrid DFT methods used in the study of these chemical transformations was assessed by comparing their energy reaction profiles with highly accurate quadratic complete basis set (CBSQ) ab initio studies.