As a follow-up to a study of oxadiaziridine, N2H2O, as a
potential high energy density material, we determine the
enthalpies of formation and combustion of a very similar
compound with an oxygen-nitrogen four-membered ring,
1,3-dioxa-2,4-diazetidine, which also would exist as cis and
trans isomers. As a fundamental measure of the reactivity of
N2H2O2, the proton affinities of both isomers were also
determined. Gaussian-2, Gaussian-3, and two complete basis
set methods were used.