Ab initio study on the mechanism of the radical reaction NNH(2A′)+N(4S)→N2+NH(3Σ−)

The mechanism of the title reaction has been studied at the UHF, UMP2, UMP4(sdq) and UQCISD levels of theory with the 6-311G** basis set. The results show that the hydrogen-atom abstraction path proceeds without potential energy barrier and the trans and cis nitrogen-atom abstraction reaction paths have quite small potential energy barriers. The heat of reaction calculated at the UQCISD level is −79.83 kcal/mol. Therefore, though the hydrogen-atom abstraction reaction is the most dominant reaction path, the nitrogen-atom abstraction reaction paths should be considered in high temperature reaction kinetics.